Installed Champion OEM spark plugs and check engine light came on

[Floridajeepcherokee]

I changed plugs today and replaced the auto lights with the Champion oem plug. I also noticed that the clamp for tailpipe leading from the glass pack had come loose and re-attached it and during test drive check engine light came on.

[4.3LXJ]

Have you got the codes yet?

[tommy guns]

I don't know codes. But i'm guessing it's a misfire,since you were messing with the plugs.

[XJ Wheeler]

Depending on the codes but is it possible you broke one (or more) of the clips off inside the plug wires?

[Floridajeepcherokee]

one wire at a time, AutoZone isn't open yet, I had changed wires no light after test drive. Then when I noticed clamp for tailpipe after the glass pack and repaired it then went for another test ride before it came on.

[Floridajeepcherokee]

http://www.p0420.com/ 420 cat converter code.

[Floridajeepcherokee]

I saw utube videos about cleaning cat converter in lieu of replacing it for 120.00. Has anyone tried cleaning a cat converter? Mine is fairly easy to remove.

[Mudderoy]

I saw utube videos about cleaning cat converter in lieu of replacing it for 120.00. Has anyone tried cleaning a cat converter? Mine is fairly easy to remove.

Hmmm cleaning it, interesting. I don't think my catalytic converter cost more than $120 shipped.

I don't think a cleaning would have fixed this though. I'm glad I had a new one at the time of taking this picture.

2859

[nickyg]

I heard that you can clean your cat out by blowing real hard into the tail pipe.

[nickyg]

HA HA just joking, I wanted to look outside and see how many people were blowing into a muffler, unfortunately I was the only one.

[Floridajeepcherokee]

LOL

[Mudderoy]

I heard that you can clean your cat out by blowing real hard into the tail pipe.

Tried it, cat scratched the hell out of me! :bacondance:

[nickyg]

Tried it, cat scratched the hell out of me! :bacondance:

Now thats funny!

[nickyg]

Tried it, cat scratched the hell out of me! :bacondance:

I wish I would've thought of that

[Floridajeepcherokee]

I replaced Cat Converter and the screen in middle like your picture didn't exist. I don't know of someone robbed it or what?

[4.3LXJ]

Check your muffler for the screen?

[Mudderoy]

I replaced Cat Converter and the screen in middle like your picture didn't exist. I don't know of someone robbed it or what?

I think you're talking about my picture. My understanding is that isn't a screen. That is the little openings that go through the material in the cat. In other words it was block, cracked and falling apart. You should see a block of material in there with those holes open, and certainly in one piece.

If nothing is in there, then someone removed the material basically turning the cat into a poor muffler. It increases exhaust flow oh and cheaper than replacing it with a new catalytic converter.

http://www.enginebasics.com/Engine%20Basics%20Root%20Folder/images/Image9.gif

[Floridajeepcherokee]

I replaced cat and muffler. The muffler looked like someone drilled 10 holes into it.

[Floridajeepcherokee]

This JGC is driving me crazy. Check engine light came back on today. it had been back firing and stalling out sometimes it wouldn't immediately start back up. I seemed to have a dead battery and it's brand new so I hooked jumper cable up from battery negative post only to engine or frame and it started without jumping it. Therefore I figured out it was loosing ground. It hasn't stalled since I tightened up the ground cable. But the check engine light came on the next day (today) The 2 codes indicated o2 sensor and thermostat (not heating up to proper temp quickly. One of the codes also mentioned defective cat converter but I had already replaced muffler and cat converter months ago.

My passenger floorboard was soaked with water and I bypassed heater core as soon as I bought it so I ruled out heater core. I also drilled out for the a/c vent and blew compressed air as mentioned in other threads. I will be trying to locate water leak or soaked carpet issue in the next few days.

[4.3LXJ]

You live in a humid climate. Check to see the condensate drain is not plugged. If they plug, when the AC is on, say like even with defrost, it will grab water vapor and it will condense and need a place to go

[tommy guns]

I've done it before. Not on a Jeep,but if you can remove it easily take a large prybar and knock all the crap out of it.

[Floridajeepcherokee]

This JGC is driving me crazy. Check engine light came back on today. it had been back firing and stalling out sometimes it wouldn't immediately start back up. I seemed to have a dead battery and it's brand new so I hooked jumper cable up from battery negative post only to engine or frame and it started without jumping it. Therefore I figured out it was loosing ground. It hasn't stalled since I tightened up the ground cable. But the check engine light came on the next day (today) The 2 codes indicated o2 sensor and thermostat (not heating up to proper temp quickly. One of the codes also mentioned defective cat converter but I had already replaced muffler and cat converter months ago. po420, and p1281 were the 2 codes

[Carves]

This JGC is driving me crazy. Check engine light came back on today. it had been back firing and stalling out sometimes it wouldn't immediately start back up. I seemed to have a dead battery and it's brand new so I hooked jumper cable up from battery negative post only to engine or frame and it started without jumping it. Therefore I figured out it was loosing ground. It hasn't stalled since I tightened up the ground cable. But the check engine light came on the next day (today) The 2 codes indicated o2 sensor and thermostat (not heating up to proper temp quickly. One of the codes also mentioned defective cat converter but I had already replaced muffler and cat converter months ago. po420, and p1281 were the 2 codes


Good ground connections are important.

PO420 Catalytic Converter Efficiency - Catalyst 1/1 efficiency below required level.

Be aware that the cat will only be faulty ... IF the O2 sensor is working correctly ;);) ... could just be a dodgy 02 sensor rather than actually being a faulty cat. Check and clean the connector ... Some have found the actual problem has been the wiring ripped off.

PO1281 ... Engine is Cold Too Long - Engine coolant temperature remains below normal operating temperatures during vehicle travel (Thermostat).

Might not be the thermostat at all ... could be a dodgy coolant temp sensor.
What sort of temp is your dash display indicating ??

[Floridajeepcherokee]

This is the normal temp reading at best unless I'm towing then it will start going towards the middle as o/d is off when towing

[Carves]

This is the normal temp reading at best unless I'm towing then it will start going towards the middle as o/d is off when towing

Looking at that pic ... I would probably be swap in a new thermostat.

... but its always worthwhile considering the temp sensor is faulty ... as its not an unknown issue.

Also ... if the gauge is relatively accurate ... That low a temp wont be doing your fuel economy a lot of good.

[prcjeep]

I'll provide you some links on how to permanantly fix you leak issue above the passenger floorboard.

If that is your normal running temp, it may have a thermostat in it that just stays open rather than one the maintains the temp around 200

[drakan1908]

My temp with the 4.0 runs about a needle width on the low side of the 210 mark. That looks a little low. This could possibly be the O2 problem also since the motor is not coming up to temp.

Sent from my XT907 using Tapatalk

[prcjeep]

This JGC is driving me crazy. Check engine light came back on today. it had been back firing and stalling out sometimes it wouldn't immediately start back up. I seemed to have a dead battery and it's brand new so I hooked jumper cable up from battery negative post only to engine or frame and it started without jumping it. Therefore I figured out it was loosing ground. It hasn't stalled since I tightened up the ground cable. But the check engine light came on the next day (today) The 2 codes indicated o2 sensor and thermostat (not heating up to proper temp quickly. One of the codes also mentioned defective cat converter but I had already replaced muffler and cat converter months ago.

My passenger floorboard was soaked with water and I bypassed heater core as soon as I bought it so I ruled out heater core. I also drilled out for the a/c vent and blew compressed air as mentioned in other threads. I will be trying to locate water leak or soaked carpet issue in the next few days.

Here's some links on solutions to what is the most common reason for having the passenger side carpet soaked.

1.http://www.jeep-club.at/troubless/TSB/24-06-96.htm
2. http://www.aircondition.com/tech/questions/4/
3. http://www.cherokeeforum.com/f52/ac-drain-location-wet-carpet-fix-24246/

The first one is a technical service bulletin from Jeep in 96. This lists the issue to apply only to 93-96, however from my understanding the issue continued for several years.

The second link above is a more in depth description and break down with photos regarding the procedure to alleviate the issue.

The third link is a "write-up" done by another Jeep owner on an online Cherokee forum, it has pictures and step by step of what he did to correct the issue.

A friend of mine used the method of cutting out the access hole to be able to put a hose extension on the drain.

[Floridajeepcherokee]

I tried the drill option. Finally I cut the carpet out to try to locate source while driving. I don't see any water now. I also haven't seen water dropping on ground. So I don't know. I'm not sure how the water got there. I'll probably hook up heater core soon and until I see water on floor I'll assume it's fixed.


The blower still defaults to defrost during heavy acceleration and higher speeds.

[Floridajeepcherokee]

new codes yesterday popped up
for accelerator pedal sensor and distributor code as well as the o2 sensor or defective cat code I previously posted. It back fired and shut off once or twice yesterday before daylight but not at all later during sunlight part of the day, 6am-4om I was running errands all day.

[Floridajeepcherokee]

Looking at that pic ... I would probably be swap in a new thermostat.

... but its always worthwhile considering the temp sensor is faulty ... as its not an unknown issue.

Also ... if the gauge is relatively accurate ... That low a temp wont be doing your fuel economy a lot of good.

I suppose after changing thermostat if gauge doesn't change that the sensor may be bad. I'm not sure where the sensor is or what it looks like. May even be two sensors. I don't know

[4.3LXJ]

One sensor located on the front of the head by the upper radiator hose

[Floridajeepcherokee]

k thanks

[4.3LXJ]

Just another thought. Since you are getting multiple codes, there are two issues you might want to consider. One is bad grounds. Redo them all. Second is the ECM. But of the two, the grounds are the most likely

[Floridajeepcherokee]

I seemed to have a dead battery and it's brand new so I hooked jumper cable up from battery negative post only to engine or frame and it started without jumping it. Therefore I figured out it was loosing ground. It hasn't stalled since I tightened up the ground cable.

.


Just another thought. Since you are getting multiple codes, there are two issues you might want to consider. One is bad grounds. Redo them all. Second is the ECM. But of the two, the grounds are the most likely

DONE already tightened 2 ground cables

[4.3LXJ]

Gotta make sure it is clean under there too

[Floridajeepcherokee]

stalling and back firing became worse. One code showed up as bad ignition coil. I replaced ignition coil and disconnect battery to reset computer. Temperature is still low. I plan to replace thermostat next because temperature runs below normal operating temperature which I assume would cause engine to run rich.

[4.3LXJ]

Yes, it would

[Floridajeepcherokee]

Here is my normal temperature according to gauge

[Floridajeepcherokee]

Argghhh!!! I'm beginning to hate Jeep. I replaced ignition coil and rotor button. I put in a thermostat as there wasn't one in it. And it still backfires and stalls out.

[Floridajeepcherokee]

This pos is really ticking me off. Two mechanics said nothing wrong with it. It keeps back firing and stalling out. No necessary at same time. It seems sometimes backing out of accelerator or lightly pumping it may prevent a stall. It's starting to not start right back up but will after time passes. It has stalled out after driving it for awhile and immediately when started (cold). If it were legal I would I burn it to the ground. Not getting much help here either. I'm nearly to the point I would never buy a Jeep product. There should be a class action law suit. I had to get pushed from a redlight to the store and it immediately started. WTH???

[Brasscatz]

So reading through your thread, it looks like you've replaced the cat, muffler, thermostat, plugs/wires, rotor, ignition coil, etc. and you still have a backfire/stall problem. I'm wondering about the condition of your throttle body. You can pick one up from the junk yard for a decent price, or try rockauto.com for great prices as well.

I'm also wondering about vacuum leaks, O2 sensors and sensors like CPS, TPS, and their connections/wiring. One way or the other, we'll try to get this resolved for you buddy.

[XJ Wheeler]

new codes yesterday popped up
for accelerator pedal sensor and distributor code as well as the o2 sensor or defective cat code I previously posted. It back fired and shut off once or twice yesterday before daylight but not at all later during sunlight part of the day, 6am-4om I was running errands all day.








This pos is really ticking me off. Two mechanics said nothing wrong with it. It keeps back firing and stalling out. No necessary at same time. It seems sometimes backing out of accelerator or lightly pumping it may prevent a stall. It's starting to not start right back up but will after time passes. It has stalled out after driving it for awhile and immediately when started (cold). If it were legal I would I burn it to the ground. Not getting much help here either. I'm nearly to the point I would never buy a Jeep product. There should be a class action law suit. I had to get pushed from a redlight to the store and it immediately started. WTH???

Whatever happened with that distributor code? If something is off with the distributor it certainly might effect the timing which could cause the backfire and stalling.

Sent via messenger pigeon - i talk, he types.

[Floridajeepcherokee]

ignition coil code, after it was just changed.

[Floridajeepcherokee]

Jeep shut off last night and two night. Mostly @ red lights. It seems like it worse during colder temps and wet climate i.e. cold, ice, early mornings in Florida. Last night was worse than tonight and
I had ice on windshield yesterday. It tried to die last night at a stop sign and I placed it in neutral as it tried to die out which prevented it from stalling. I may have slightly revved accelerator. revving slightly or backing out sometimes prevents or prevents it from stalling out.


I called Auto Zone about fuel filter and was told it is $112.00 for fuel filter which is also a fuel regulator according to Auto Zone. Please help, I recently became re-employed which means I'm on job probation. I can be let go for tardiness or car troubles and attendance.

[Floridajeepcherokee]

Getting worse and wont start right back up. Turning key off and wait then starts right back up. It started with stalling but would start right back up now it takes awhile.

[nickyg]

have you tried the crank position sensor or the distributor pick up sensor? If you haven't replaced em recently it might be worth a shot.

[Brasscatz]

I don't remember seeing that you cleaned or replaced the idle air control valve. That may help with it stalling.

Sent from my Samsung Galaxy S4 because my microwave couldn't do it

[tommy guns]

However unlikely it may be,it could be a bad ECM.I've seen it before,not on a Jeep,but it happens. They can go haywire and just throw random codes. I would replace the CPS also.

[nickxj94]

I would rule out the cps also.

[Floridajeepcherokee]

This is all over the internet. Which is evident when u search grand Cherokee stalling. I can't afford to keep changing part after part. However putting in neutral, backing out or slight reving seems to help prevent it from stalling. It spits and sputters.

[Floridajeepcherokee]

1996 - 2000 Jeep Dying Problem Road Test DyingJeep.Com - YouTube

[Brasscatz]

interesting... although I don't know if I trust them. What if it doesn't work or their "fix" ends up ruining your pcm? You've just paid those guys some of your hard earned $$$ for nothing.

[Brasscatz]

Give this a read... this may be that $20 solution that video was talking about. If this fixes it... I promise not to charge you :D

http://forums.cnet.com/7723-7811_102-248386/jeep-grand-cherokee-stalling-fixed/

[Brasscatz]

More specifically, here is a guy's post on EXACTLY what dyingjeep.com tells you to do.

"solution to your problems
My jeep stalled and backfired and died for three months. It drove me crazy. I did everything everyone else did replacing alternator fuel pump water pump crank shaft sensor other sensors i mean just the monetary nightmare. Thene one morning i run into a post on the internet. DyingJeep.com The guy wanted 20 bucks for the solution. I figured what the hell, whats 20 bucks. low and behold the **** worked. Im still at a loss of wordss... So I'm going to give it to you free today because if your like me I know what you have gone through. This fix is a combination of all the other solutions I have read over 3 months with my problems of backfiring stalling sputtering and the like. takes 30 minutes or less

First unhook the battery cables second remove the overflow tank next on your computer on the firewall remove the three plugs that connect into the computer then you will see the two little screws that people talk about backing out (the screws short the system out) remove the screws one at a time ande add 3 8 mm washers to each screw then replace them. Next take a good electrical cleaner spray and spray the plugs and the connectors where they pug in. Spray them well to insure there clean. Let dry about 10 minutes. then take some dialectric electrical silicone and put on plugs in each hole and then in the connector spots they plug in. (this creates a better seal and connection) Plug the plugs back in. The plugs only fit where they are suppose to go so you cant go wrong. Now that the plugs are in take 24 inch zip cordes and wrap around the computer and the plugs you just plugged in. 2 cords per plug and pull each cord snug to put pressure on the plugs. 2 cords per plug cut off the remaining cord hanging off the cord. When its done. your computer will have 6 zip ties wrapped around it forcing the 3 computer plugs into the system. Thats it..... Simple and works..... I'm still amazed. i paid 20 bucks for this fix. If you cant understand what I just shared with you for free you can go to dyingjeep.com and pay 20 bucks and see the guys step by step video. I hope this helps somebody out there. Like I said Im only sharing it because my jeep just about drove me crazy and broke me.... The **** worked and i'm still amazed....20 bucks good lucl....

Just a guy that wants to help"

[Floridajeepcherokee]

interesting... although I don't know if I trust them. What if it doesn't work or their "fix" ends up ruining your pcm? You've just paid those guys some of your hard earned $$$ for nothing.

Agreed, I posted video to show it's common and I'm not crazy. My Jeep idles under 1000 until I place it in gear. I was also considering looking at or cleaning IAC.

[Floridajeepcherokee]

Today, I put sea foam in throttle body, I cleaned IAC, and backed two screws in PCM out slightly. Still idles about 750 RPM"S.

[Brasscatz]

Today, I put sea foam in throttle body, I cleaned IAC, and backed two screws in PCM out slightly. Still idles about 750 RPM"S.

I'd have to check, but I'd swear my Jeep idles around 750 too. Did it still sputter and die?

[drakan1908]

http://img.tapatalk.com/d/13/12/04/u3ybypu2.jpg


This is my ZJ idling. Where is yours?

Sent from my XT907 using Tapatalk

[Floridajeepcherokee]

same idle point as Drakan, it didn't sputter or stall today but didn't go far and mornings or late night when going to and from work has been the worse.

[Brasscatz]

same idle point as Drakan, it didn't sputter or stall today but didn't go far and mornings or late night when going to and from work has been the worse.

This is still very promising! Keep us updated man! I have my fingers crossed ;)

[Floridajeepcherokee]

Check engine light came back on but no back fire or stalls today or yesterday.

[Brasscatz]

I call that progress! I am guessing that the CEL and backfire/stalling are 2 separate issues... and I'm hoping that one of them is solved! What's the code on the CEL showing now?

[nickyg]

Today, I put sea foam in throttle body, I cleaned IAC, and backed two screws in PCM out slightly. Still idles about 750 RPM"S.

X2 My jeep idles a hair above the 500 rpm mark. I guess it's 600 to 700.

[Floridajeepcherokee]

I call that progress! I am guessing that the CEL and backfire/stalling are 2 separate issues... and I'm hoping that one of them is solved! What's the code on the CEL showing now?

Haven't pulled it yet, It may be an active code from before. I'm just glad I made it to and from work without stalling nor backfire.

[Floridajeepcherokee]

Another day no stall, no backfire.

[Brasscatz]

Another day no stall, no backfire.

:bacondance: :bacondance: :bacondance: :bacondance: :bacondance:

:spongebob: :spongebob: :spongebob: :spongebob: :spongebob: :spongebob:

:banana: :banana: :banana: :banana: :banana:

:smiley-dance015: :smiley-dance015: :smiley-dance015: :smiley-dance015: :smiley-dance015:

:smiley-dance011: :smiley-dance011: :smiley-dance011: :smiley-dance011: :smiley-dance011:

:beavis: :beavis: :beavis: :beavis: :beavis:

:smiley-bounce015: :smiley-bounce015: :smiley-bounce015: :smiley-bounce015: :smiley-bounce015:

:toothorn: :toothorn: :toothorn: :toothorn: :toothorn:

[Floridajeepcherokee]

I drive an hour to work. Recently became re-employed. How long should I wait before I start giving me only driving time to work? I work for state and I'm new so I can't be late. I've been leaving 2-3 hours early to ensure I was on time.

[Brasscatz]

Ouch... hard to say buddy. I applaud you being responsible and leaving so early to make it in on time, but I don't know... a week? 3 days? I'd maybe say if it hasn't done it in 5 days in a row, leave at regular time. Maybe start leaving a little later each day until you're leaving at normal time

[Floridajeepcherokee]

Ok Thanks, I don't like being late, and certainly cant afford to be late especially now.

[xj4life2]

Ok I'm just gonna jump in here for a quick 2 cents, Backfiring is a timing issue so I would go after the Dist get one from a junk yard and try it be sure you set it up correctly , the fact that it dies at stop signs and red lights and you have to rev it up to keep it running could also be a timing issue , yes timing on these is controlled by the ECM but the Dist. must be in good working order. If it were me and after all the swapping you have done I would JY me a Dist and an ecm swap them in one at a time and see if your back on the road. Beyond this I would take it in and have properly diagnosed so you quit throwing money at and get it fixed for good.

[Floridajeepcherokee]

Ok I'm just gonna jump in here for a quick 2 cents, Backfiring is a timing issue so I would go after the Dist get one from a junk yard and try it be sure you set it up correctly , the fact that it dies at stop signs and red lights and you have to rev it up to keep it running could also be a timing issue , yes timing on these is controlled by the ECM but the Dist. must be in good working order. If it were me and after all the swapping you have done I would JY me a Dist and an ecm swap them in one at a time and see if your back on the road. Beyond this I would take it in and have properly diagnosed so you quit throwing money at and get it fixed for good.


Today, I put sea foam in throttle body, I cleaned IAC, and backed two screws in PCM out slightly. Still idles about 750 RPM"S.

Why? After I did the above no back fire or stalls since.

[Brasscatz]

So, any good updates for us? :pray:

[Floridajeepcherokee]

95 percent better, I think it tried once today. It shut off the other day at idle but it was intolerable before so its either fixed or lot better.

[Brasscatz]

I'll take it :D

[Floridajeepcherokee]

I'll take it :D

Deal, 2 grand and its yours. : )

[Brasscatz]

Lol, Monopoly money ok?

[Floridajeepcherokee]

it's getting worse again. It stalls about daily. I bought a can of starting fluid. it stalled tonight and wouldn't immediately start. I sprayed it and it started . I'm thinking it is losing fuel pressure and maybe I need to change filter and fuel pump which I heard are both located in the fuel tank. I'm thinking when it doesn't immediately start it is losing fuel pressure. And when it stalls and starts back quickly that it is catching prime again. Any thoughts? I don't want to nickel and dime it. It started acting up again about a week later and is getting worse like 3 or 4 times daily again.

[Floridajeepcherokee]

I sprayed carb cleaner in throttle body and seemed better for about a day.

[Floridajeepcherokee]

Lol, Monopoly money ok?



Not exactly..

You: "I'd like a Coke."
Waiter:"Is Pepsi ok?"
You: "Is Monopoly money ok?"

[4.3LXJ]

If you can find a fuel gauge to hook up you could verify that easily by monitoring the pressure under high rpms

[Floridajeepcherokee]

If you can find a fuel gauge to hook up you could verify that easily by monitoring the pressure under high rpms



http://www.doityourself.com/stry/warning-signs-of-a-bad-crankshaft-position-sensor#.Ut9C2bAo7IU



Warning Signs of a Bad Crankshaft Position Sensor




By
DoItYourself Staff











Editor's Picks
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Modern automobile engineering has made the crankshaft position sensor an important part of the car’s engine. This small device is instrumental in monitoring the engine’s multiple components via the car’s computerized engine management system. The sensor tracks the speed of crankshaft rotation. It also monitors the engine valves in relation to the pistons, and observes overall engine function.

The crankshaft position sensor is usually placed on the crankshaft of near the main pulley. It passes on information, and as with any other component of the engine, when things begin going south, it needs immediate attention. Ignoring the symptoms of a bad crankshaft position sensor will result in rapid wear and tear of the various parts of the engine and will lead to rapid engine wear-out. Fortunately, warning signs of a bad crankshaft position sensor are easy to detect by the driver. Read through the following points and keep an eye out for any one of these warning signs.



The Blinking of "Check Engine" Light

The simplest and most obvious symptom of a failing crankshaft position sensor is the blinking “check engine” light in your car. Fortunately, this light is programmed to come on well in advance, allowing you to take care of the problem before the car is left immobile and you are left stranded. Once the light comes on, be sure to contact your mechanic for a quick look-over or take your car for servicing.

Ignition Malfunction

When the crankshaft position sensor begins to fail, the signal it transmits to the vehicle’s computer begins to weaken. If left unattended, the signal will switch off completely. This, in turn, causes the car’s spark plugs to die out, killing the engine. If you are having problems starting your car, it could indicate bad crankshaft position sensor.

Stalling and Backfiring

Another sign of a sensor malfunction is the constant stalling and backfiring of the engine. In such a scenario, the engine is prone to getting cut-off from time to time, stalling as you drive for a few seconds. Unlike ignition malfunction, the car will probably start, even run for a while, only to shut down somewhere along the way. It goes the same for engine backfiring. If you keep ignoring the warning signs though, the engine may get exhausted and die out.

Engine Vibrations

As mentioned above, the sensor regulates the crankshaft position. Once the position sensor begins to fail, you’ll notice a considerable increase in engine vibration. This in turn will ruin your mileage as well as engine power.

Other Disruptions in Engine Function

One of the most common effects of crankshaft position sensor failure is visible on the engine function of your car. As the sensor utility deteriorates, it affects regular functions like acceleration, ignition, idling and speed fluctuations. Each of these functions experience abnormal patterns, resulting from actions not initiated by the driver. If you are experiencing any such car troubles—sudden disruption in acceleration, for example—it might be time to overhaul the crankshaft position sensor.


Read more: http://www.doityourself.com/stry/warning-signs-of-a-bad-crankshaft-position-sensor#.Ut9Dd7Ao7IV#ixzz2r641CPe9

[Floridajeepcherokee]

seems like it is dieseling when it stalls out. I'm wandering if it's the cps.

[Floridajeepcherokee]

I had crankshaft position sensor changed. A new code popped up tonight. I also changed both o2 sensors tonight. Still backfiring and check engine light just came back on. it's driving me crazy. It also only stalled tonight at idle since the replacement listed above. Coil was changed awhile back and code was showing tonight for ignition coil. I had no check engine light then light came back on tonight.

[4.3LXJ]

Check your distributor cap for cracks and dirt lately?

[gary63]

you may have a valve that is not rotaiting do to carbin on the stem. seafoam may remove it but most of the time you have to use it and then remove valve cover and comprish spring rotate the valve a1/4 of a turn and put it back to gether and run it again.

[Floridajeepcherokee]

Check your distributor cap for cracks and dirt lately?


LOL But no that was my next part to change. I did change rotor button awhile back.


you may have a valve that is not rotaiting do to carbin on the stem. seafoam may remove it but most of the time you have to use it and then remove valve cover and comprish spring rotate the valve a1/4 of a turn and put it back to gether and run it again.

Hmm, This issue is all over the internet as in extremely common. I highly doubt it's a valve. I have used several injector cleaners and sea foam numerous times.

[gary63]

The valves are supposed to rowtate and they sometimes stop and then they build up corbin on the seats. It is common anif that chry.and jeep have put out a costumer advicery on it.

[Floridajeepcherokee]

replaced distributor cap.

[Floridajeepcherokee]

It may still be doing it not sure. Bought a code scanner. Someone mentioned it could be fuel pump and filter in the tank. But why is it erratic? I may have crossed the spark plug wires. Anyone know which wire goes where from the distributor cap to the spark plugs on a 98 4.0 L Grand Cherokee?

[drakan1908]

Sent from my XT907 using Tapatalk

[4.3LXJ]

If you did that, the 300 codes will tell you which ones to switch

[Floridajeepcherokee]

If you did that, the 300 codes will tell you which ones to switch

After posting I looked on line and found these diagrams. I put tape on my wires just now and labeled current position then drew on a paper and came inside it looks like your diagram u posted. I'm headed to work shortly.
My screw holes to mount distr. cap are between 3 and 5 and between 2 and 4 like u posted. But based on internet pics I found previously they show screw holes between 3 and 6 and 1 and 4. Which one is correct??

After installing yesterday I did a test drive and pulled over and switched wires and final result is how it is now.....I pulled over b/c check engine light was flickering intermittingly but wouldn't stay on and it sounded like crap. It sounded good when I drove home but when I left work last night it wouldn't start at first.

[Floridajeepcherokee]

This online pic shows it like the others. I would think plug wires wrong could definitely cause the backfiring. In fact it was backfiring a lot after the distr. cap replacement.

[4.3LXJ]

It looks like you have the wires all rotated a little. You have to have the distributor timed properly for it to run right. The computer can make up for some of it, but not entirely. Tony has a thread on here on timing the dizzy. You might want to PM him and ask for the link

[Floridajeepcherokee]

My wires are exactly like Drakkan posted. The internet shows different than Drakkan but my wires are exactly like Drakkan posted above.

[Floridajeepcherokee]

I'm asking should the left side screw hole that holds the left side of distributor cap be between the 6 and 3 or between the 3 and 5 like Drakan1908 posted above??

[Floridajeepcherokee]

2 days in a row the jeep didn't want to start. It didn't want to start today before I left for work and I shot it with starting fluid and it started, This would indicate or confirm the fuel pump. At this point my last 2 options are replacing the fuel pump, regulator and filter in the tank or pcm as a final option. Pcm cost more than the fuel pump items.

[drakan1908]

I would go get a picture of mine but it is 16 degrees and snowing. Just got home from working out in this crap. I'll try to get you a picture in the morning. I took that pic of my Haynes manual but I'm pretty sure mine looks like that.

Sent from my XT907 using Tapatalk

[Floridajeepcherokee]

I would go get a picture of mine but it is 16 degrees and snowing. Just got home from working out in this crap. I'll try to get you a picture in the morning. I took that pic of my Haynes manual but I'm pretty sure mine looks like that.

Sent from my XT907 using TapatalkOk thanks but probably take like 10 seconds ..if u look at the screw holding the distributor on the one closer to the passenger seat not the one facing the radiator is the wire going to the last cylinder number 6 above that screw or is the wire above that screw going to the 3rd cylinder.

[drakan1908]

http://img.tapatalk.com/d/14/01/29/buzajupy.jpg

http://img.tapatalk.com/d/14/01/29/azejumu2.jpg


Here is a couple of pics of mine.

Sent from my XT907 using Tapatalk

[Floridajeepcherokee]

On the second pic...the last plug on the left side is which cylinder?? see the screws holding the distributor cap?? the one on the opposite side of the radiator.

[drakan1908]

In the second pic- left of the coil wire from bottom to top 5,3,6 right of coil wire 1,4,2.

Sent from my XT907 using Tapatalk

[Floridajeepcherokee]

The blue arrow and circle is which cylinder?
There should be a screw beside dist. cap holding it on (yellow and red arrows) Yellow one should be the one I was referring to earlier.

[drakan1908]

Blue circle#1

Sent from my XT907 using Tapatalk

[Floridajeepcherokee]

looks like cylinder number 2 because pic 1 shows 2 spark plugs right of the coil.See what I mean???

[Floridajeepcherokee]

Looks like it is cylinder number 2 not 1. Agree??

[Floridajeepcherokee]

Based on your diagram and pic it's cylinder number 2

[drakan1908]

That is cylinder #2 with the blue circle. Red arrow is #1 Sorry was in a hurry

Sent from my XT907 using Tapatalk

[Floridajeepcherokee]

Ok Thanks, u were starting to really confuse me LOL.

[drakan1908]

Ok Thanks, u were starting to really confuse me LOL.

Haha welcome to my world, I stay confused

Sent from my XT907 using Tapatalk

[Floridajeepcherokee]

code po351 popped up and I have a new coil. Is my coil bad??

[Floridajeepcherokee]

Shop checked fuel pressure and said it was 45.

[Floridajeepcherokee]

po351 for coil and PO108 map sensor high voltage codes are showing. Put in another coil new and and a used map sensor. codes still on. This jeep is pissing me off totally.

[Floridajeepcherokee]

P0108 - MAP Pressure Circuit High Input
P0351 Ignition Coil A Primary/Secondary Circuit Malfunction

[drakan1908]

Did you try your old MAP sensor again? I wondering if you have a faulty ECM.

Sent from my XT907 using Tapatalk

[Floridajeepcherokee]

PCM and fuel filter assembly are my last guesses. I honestly would set it on fire if it were paid off. (NOT INSURANCE FRAUD)

[Floridajeepcherokee]

@ my wits end with it.

[Floridajeepcherokee]

I replaced map sensor with a used one still dying.

[Brasscatz]

I would do the filter assembly and see what happens.

[4.3LXJ]

Did you try your old MAP sensor again? I wondering if you have a faulty ECM.

Sent from my XT907 using Tapatalk

At this point, I am thinking the same thing

[Floridajeepcherokee]

more money....

[Floridajeepcherokee]

would a used pcm from junk yard just plug in??

[4.3LXJ]

Yes

[Floridajeepcherokee]

Oh thought it had to be programmed.

[4.3LXJ]

No, you can pull one for that year and just plug it in.

[Floridajeepcherokee]

Drove to work no stall. On the way home, like 4 or 5 stalls. I pushed the valve stem and a lil gas came out then it started. I push it running and it was a steady stream. Sometimes I would spray with starting fluid and it would start. I believe it's a fuel issue. But whatever it is, is erratic.

[Floridajeepcherokee]

2 nights of stalling and starts with starting fluid sprayed. Almost got run over when a car started hydroplaning and skidding after a curve coming straight towards me.After stall I pressed the shrader valve and a little gas came out then nothing.



Is it possible to distinguish the problem coming from fuel pump or fuel pump relay?

[4.3LXJ]

Fuel pump relay should be on whenever the Key is turned

[gary63]

have you pulled some fuel out from the fuel line at the engin or have you dropped the tank and check the tank for junk floating inside that might plug the line and then unplug?

[Floridajeepcherokee]

Ok today driving to work it stalled or tried and didn't do much tonight but tried once or twice. I replaced horn and fuel pump relay so its not the relay because it still back fired and tried stalling, If it were the pcm I cant see throwing it in neutral and revving it slightly which seems to prevent the stall....as a pcm issue. As of now I'm thinking pressure regulator, filter and pump replacement.

Someone else said it was the cat on his Jeep, which I replaced recently already. So if I remove the front o2 sensor like it said it would indicate whether the cat is to blame again. Because it would create an opening to bypass the cat. As of right now I plan to have the filter, pump, and fuel regulator replaced on next payday and day off.

If it were the pcm I can't see spraying the throttle body and it restarting when it stalls and doesn't want to start. My tank will be nearly empty when payday gets here. I'm going to have a mechanic look at it before doing the replacement. Last mechanic said nothing was wrong. The fuel pressure reading the other day was within specs...but it wasn't acting up. I read the fuel pressure regulator can cause the backfire and stalling. I don't have any current active codes. If I don't get this fixed soon I will probably never own another Jeep product. I love the way it drives except for the stalling and backfiring. I almost got wiped out last night by a behicle when it stalled and I pulled into ditch by a curve. What do u think???

[Brasscatz]

I think that you're on the right track with the fuel assembly. It's to the point where we're running out of possible culprits. I hope it doesn't fully turn you off of Jeeps, this doesn't happen to hall of them :D but I understand your frustration completely

[Floridajeepcherokee]

I read o2 sensors have a fuse or 2 so that's also on my check list.

[Brasscatz]

Yep, they do. When I was looking at my jeep before I bought it, it was throwing a check engine code for the o2 sensor. The guy had gone in and tried messing with the fuses, but was referencing the diagram for the relay box under the hood by accident. I fixed his problem before I purchased it LOL. Also turned out the o2 sensor wire was shorting and blowing the fuse out so I spliced in some new wire. Fixed it right up

Sent from my Samsung Galaxy S4 because my microwave couldn't do it

[Floridajeepcherokee]

Yep, they do. When I was looking at my jeep before I bought it, it was throwing a check engine code for the o2 sensor. The guy had gone in and tried messing with the fuses, but was referencing the diagram for the relay box under the hood by accident. I fixed his problem before I purchased it LOL. Also turned out the o2 sensor wire was shorting and blowing the fuse out so I spliced in some new wire. Fixed it right up

Sent from my Samsung Galaxy S4 because my microwave couldn't do it

I looked in fuse box this morning under hood didn't see an o2 labeled fuse.

[Brasscatz]

I looked in fuse box this morning under hood didn't see an o2 labeled fuse.

If I remember correctly, the fuse for the o2 was in the interior fuse box. The guy was just trying to use the relay box diagram for it. Do you have an owner's manual for your Jeep? Should have all the fuses labeled in there for ya

[drakan1908]

No listing for an O2 sensor in internal fuse box.


http://img.tapatalk.com/d/14/02/04/yzebu2ah.jpg

http://img.tapatalk.com/d/14/02/04/e9e3yza3.jpg

http://img.tapatalk.com/d/14/02/04/dutu5u6a.jpg

http://img.tapatalk.com/d/14/02/04/apyge6y7.jpg

http://img.tapatalk.com/d/14/02/04/agasu7ap.jpg

[Floridajeepcherokee]

I was told it was the pick up coil or camshaft position sensor. This part: http://www.autozone.com/autozone/parts/Duralast-Pick-Up-Coil/1998-Jeep-Grand-Cherokee-2WD/_/N-ja2f5Z9n80y?itemIdentifier=293160_0_0_ Going to try this part. had po351 again for code. Fuel pressure looked good and today it was actually acting up at mechanic.

[Floridajeepcherokee]

fuel pressure showed good the whole time it acted up at a shop. Mechanic recommended pick up coil. Replaced pick up coil. Still activing up but rpm tach does quick rapid movement when it misses or acts up. PO351 keeps popping up.
New parts:
Cat converter
plugs, wires
coil
rotor button
dist. cap
crankshaft pos. sensor
pick up coil

[4.3LXJ]

fuel pressure showed good the whole time it acted up at a shop. Mechanic recommended pick up coil. Replaced pick up coil. Still activing up but rpm tach does quick rapid movement when it misses or acts up. PO351 keeps popping up.
New parts:
Cat converter
plugs, wires
coil
rotor button
dist. cap
crankshaft pos. sensor
pick up coil

The tach measures number of spark pulses. So if that needle starts jumping then the spark from the coil is eratic.

Sent from my DROIDX using Tapatalk 2

[Floridajeepcherokee]

why is it erratic??

[4.3LXJ]

why is it erratic??

I am not there to help you on that one. But look all conections involved and that new pickup in the dizzy. Coil.too maybe

Sent from my DROIDX using Tapatalk 2

[Floridajeepcherokee]

Think I'm going to replace IAc bc when I unplug it basically nothing happens and I seem to quit stalling after cleaning it last time. If that don't work PCM/ECM may be next.

[Floridajeepcherokee]

Please help....The jeep Grand cherokee has been better then recently it stalled out. Today it stalled out 3 times and didn't want to start. It;s sitting in driveway and won't start now. it may start in 5 minutes or in an hour. Today it started stalling out and wont re-start generally. The other day I pulled 3 codes PO320, PO351, and P1391. I reset codes then today it showed PO351 and PO320 and technically is dead in the driveway. It may start in 30 minutes but probably for no more than 20 seconds before it stalls. I have replaced IAC, both o2 sensors, coil, pick up coil and crankshaft position sensor and it got better like 100-95% better till now. Unfortunately I didn't use mopar parts. Today it rained which generally was when i had problems and generally a crankshaft position sensor problem clue to my understanding. PLEASE HELP.

[Floridajeepcherokee]

Please help....The jeep Grand cherokee has been better then recently it stalled out. Today it stalled out 3 times and didn't want to start. It;s sitting in driveway and won't start now. it may start in 5 minutes or in an hour. Today it started stalling out and wont re-start generally. The other day I pulled 3 codes PO320, PO351, and P1391. I reset codes then today it showed PO351 and PO320 and technically is dead in the driveway. It may start in 30 minutes but probably for no more than 20 seconds before it stalls. I have replaced IAC, both o2 sensors, coil, pick up coil and crankshaft position sensor and it got better like 100-95% better till now. Unfortunately I didn't use mopar parts. Today it rained which generally was when i had problems and generally a crankshaft position sensor problem clue to my understanding.

[4.3LXJ]

the PO1391 is loss of crankshaft or camshaft position sensor signal. The CMS is in the distributor. to check to see if that is working, turn it over with key on and pull the coil wire at the dizzy and put a phillips screwdriver in the end and hold it close to the engine. If you get spark, it works and then you will need to replace the crankshaft position sensor

[Floridajeepcherokee]

the PO1391 is loss of crankshaft or camshaft position sensor signal. The CMS is in the distributor. to check to see if that is working, turn it over with key on and pull the coil wire at the dizzy and put a phillips screwdriver in the end and hold it close to the engine. If you get spark, it works and then you will need to replace the crankshaft position sensor

Thanks, i disconnected positive cable went inside then came back out later and it started. I drove a few blocks then it shut off. I had to be jumped off twice from trying to start it. It finally started a second time and I drove it home. My battery is now low so it's on the charger. I assume you mean disconnect the plug type wirw coming from coil going to distributor and ground it when screwdriver touching engine block and the lead from plug type wire coming from coil. When do I do this, now? It started 3 times since I posted earlier but since then when it would shut off the engine would just spin and spin and not start. Using your test procedure I would think I would at least see spark when the engine would start...since this seems like an erratic problem but becoming more frequently. Could I see spark now and not later and if I do is it the crankshaft pos. sensor or the coil or pick up coil?

[Floridajeepcherokee]

cms is pick up coil"

[Floridajeepcherokee]

I just went outside and started Jeep with battery hooked to battery charger. Jeep started and check guages light is on. My multimeter is showing less than 9 volts with engine running and battery charger hooked up. Now I'm wondering is alternator going out and causing vehicle to shut off or did i just try to over start it tonight. Then again my multimeter should be showing at least 13 volts. I remember qwhile back i thought my alt was going out due to a readout on one of my multimeters and went to auto parts store but was told alt was good.

[4.3LXJ]

I think you should get that battery fully charged and go from there

[Floridajeepcherokee]

?????

[Floridajeepcherokee]

the PO1391 is loss of crankshaft or camshaft position sensor signal. The CMS is in the distributor. to check to see if that is working, turn it over with key on and pull the coil wire at the dizzy and put a phillips screwdriver in the end and hold it close to the engine. If you get spark, it works and then you will need to replace the crankshaft position sensor

I think you can help me. I charged battery all night (13 volts on charger, before leaving) I started Jeep and went one block and it shut off. I drove it back home. Then I tried checking like you suggested when it shut off and wouldn't start. The engine was turned over and over and I didn't see spark then all of a sudden I saw spark and out it back on and it started. What if i see spark one moment and not the other?? Which part to replace??

After charging and going one block and back my volt meter dropped and I put a multimeter on the battery and eventually it dropped to 10 volts or less while running....using 2 different multimeter simultaneously to check the volts and both dropped around 10 volts DC or less. I know alternator can shut engine down but I don't know where it would stop it from starting unless the battery dies or drops too low.

[4.3LXJ]

If you have the no spark issue, then it is likely the cam position sensor is the culprit. This sensor is responsible for getting the coil to go to ground and make a short duration spark. It is located on the distributor plate inside the distributor.

[Floridajeepcherokee]

If you have the no spark issue, then it is likely the cam position sensor is the culprit. This sensor is responsible for getting the coil to go to ground and make a short duration spark. It is located on the distributor plate inside the distributor.

The pick up coil?
My question is since my Jeep will run now then shut off and not want to start that would make sense that I would see spark one moment and not the other. So then what? What if I see spark one moment but not the next?

[4.3LXJ]

It means the sensor is going bad, and has intermittent operation as many sensors do

[Floridajeepcherokee]

It means the sensor is going bad, and has intermittent operation as many sensors do

I replaced the pick up coil this year .It wasnt Mopar part though.

[Floridajeepcherokee]

It means the sensor is going bad, and has intermittent operation as many sensors do

I replaced the pick up coil this year in February but Auto Zone gave a 3 month warranty.

[4.3LXJ]

It is just a fact that sensors are not what they used to be. I got that from a GM parts counter as I returned one that was bad right out of the box. But if you test it and it is bad, it does not matter how old it is.

[Floridajeepcherokee]

Should I see a constant spark every time I turn the key?

[4.3LXJ]

If it is turning over with the key on, then yes, constant spark

[Floridajeepcherokee]

What would indicate a bad crankshaft position sensor?

[Floridajeepcherokee]

codes are po320, po351. and p1391

[Floridajeepcherokee]

Yesterday, I was getting down to 10 volts with the engine running per my multimeter. So my first priority is to get my volts up to par first. I read the voltage regulator for Jeeps is not in the alternator. Is this true? 1998 Jeep Grand Cherokee 4.0L Do I need an alternator or a pcm. http://www.justanswer.com/jeep/7b84q-think-alternator-jeep-grand-cherokee-bad-how.html

[4.3LXJ]

Take your alternator down to an auto parts store and have them test it

[Floridajeepcherokee]

I will when I can. i saw spark sometimes with the newer pickup coil. i replaced with the old one when it started shut off and didn't want to restart. i put old pick up coil back in and don't see spark either. I checked for spark with the newer one before replacing with the older pick up coil didn't see spark either time...I want to say it's the crankshaft position sensor not being replaced with a mopar one though. I pulled battery and put back on charger.

[Floridajeepcherokee]

anyway to test the coil?

[Floridajeepcherokee]

Can I use a test light for a spark tester?

[Floridajeepcherokee]

I just switched batteries and got it running twice. however non of the guages worked and ignition wouldn't shut it off with the key. I think alternator is much of my problem. Several lights like airbag were lit up and when i disconnected the plus cable the engine shut off.

[Floridajeepcherokee]

Would a bad alternator and or low battery cause no spark? I changed battery and got it started...no tach or fuel gauge. no volt meter, etc and the fuel light and abs light stayed on. engine wouldn't shut off until I disconnected the positive cable.

[4.3LXJ]

It could. get your voltage straightened out and go from there. at 10V stuff starts not working

[Floridajeepcherokee]

Like my dash lights and tach, LOL. I tried running it last night with charger on it and it's still doing weird stuff.

[Floridajeepcherokee]

I put on a new alternator even though it tested good, because when i disconnect positive cable it would shut off making believe alternator is not charging. . My digital volt meter shows 9-12.40 volts with the engine running. I tried checking grounds. I read codes and P1682 popped up. I'm at a loss.

[4.3LXJ]

What do you have running when this happens

[Floridajeepcherokee]

What do you have running when this happens

Don't remember....

My battery tested bad according to auto part store. Can a battery charger mess up batteries? I put a digital volt meter probes on charger with no battery and no volts were showing...so is this how i test my battery charger to see if it's broken? I had it set at the 20 volt dc setting.

[4.3LXJ]

If your battery is bad, I suggest you fix that. All the electronics nowadays need a solid electrical source to function properly

[Floridajeepcherokee]

If your battery is bad, I suggest you fix that. All the electronics nowadays need a solid electrical source to function properly

P1682, PO320, and PO351 are my codes. I replaced the battery which tested bad. It's still shutting off. Battery shows 12.25 before i start it then it drops to low 12 volts with it running. i tried wiggling various wires running from alternator. Jeep started then shut off several times and won't technically start. I can disconnect positive cable then go back out and it run then shut off. The battery was under warranty from battery source. This is the 2nd replacement battery in one year which is all I can say about Battery Source is they are good about replacing batteries. I'm kind of at a loss. A brand new battery and alternator and can't get it to 14 volts or 12.5 volts even with it running engine revved and ac on or off. I don't see any shorts or broken wires.

[oderdene]

guess it's a time to replace alternator. maybe test shows good, try to check another shop. If you decided to replace, choose high output one. ZJ 136A requires little trimming of bracket, we have lots of choice.

P1682 (G) Charging System Voltage Too Low Battery voltage sense input below target charging voltage during engine operation and no significant change in voltage detected during active test of generator output circuit.

P1682 Charging System Voltage Too Low Charging system output voltage low.

P0320 (M) No Crank Reference Signal at PCM No reference signal (crankshaft position sensor) detected during engine cranking.
P0320 (M) No RPM Signal to PCM (Crankshaft Position Sensor Signal to JTEC) A CKP signal has not been detected at the PCM.


P0351 (M) Ignition Coil # 1 Primary Circuit Peak primary circuit current not achieved with maximum dwell time.

OBD2 code reference here http://www.xjtalk.com/showpost.php?p=118979&postcount=2

[Floridajeepcherokee]

volt meter doesn't show even 13 volts running. it will start then st off and maybe or generally later it will start again. I generally remove positive cable after it stalls take a break replace plus cable and it will start. I checked ohms and it shows alternator and battery and engine are all grounded. I upgraded to above 90 amp alternator allegedly.


coil, crank pos. sensor and pick up coil were all recently changed, and coil changed twice. dash volt meter indicates below 13 volts as well.

[4.3LXJ]

At this point, I think you need to consider an new PCM. Multiple codes and the voltage problem with new stuff is not a good sign

[Floridajeepcherokee]

charging issue corrected...small wire had a break (green wire one of 2)

[4.3LXJ]

Alright, now it is time to look at the rest of it. See if it still does that stuff

[Floridajeepcherokee]

The next day it wouldn't start. it finally started and stalled at least 5 times in 20 mile trip. Then wouldn't start at all until I put the old coil on so I drove to Auto Zone and replaced coil which is under warranty. What would cause a coil to need to replaced twice in 8 months? PO108 came up the other day. " - Faulty Manifold Absolute Pressure sensor
- Manifold Absolute Pressure harness is open or shorted
- Manifold Absolute Pressure sensor circuit poor electrical connection
- Faulty Engine Control Module (ECM)

Read more: http://helpforcars.net/obd_codes/p0108_jeep.html#ixzz3CSatFsqK " But now my jeep is running again. Any way of testing for a bad ECM??
What would cause ignition coils to need 2 replacements in less than one year??
My tachometer is still pinging (quick sudden slash of the rpm needle like a misfire) Has done this since i replaced the pick up coil in February which is now out of warranty b/ c it only had a 3 month warranty.

[4.3LXJ]

Coils can go bad. I have replaced two recently and now I carry a spare. An ECM can throw a code that it is bad or not. Sometimes that is an experimental thing

[Floridajeepcherokee]

Coils can go bad. I have replaced two recently and now I carry a spare. An ECM can throw a code that it is bad or not. Sometimes that is an experimental thing

Would you replaced the ECM if the jeep is running now?? PO351 and PO320 are the 2 most common codes I've observed this year to the point I'm sick of seeing them. My tachometer is like a whip (pinging) suddenly rising and falling erratically like a misfire. Right now jeep is running again.

[4.3LXJ]

No I wouldn't. But you have found one bad wire, I would look for more bad wires or connections

[Floridajeepcherokee]

stalled tonight PO320 and PO351 as usual....actually considering getting another vehicle non JEEP (after all the problems with this one.It has a misfire...new plugs cap plug wires rotor, pck up coil, coil etc....

[Floridajeepcherokee]

I had spark plugs checked then a mechanic recommended a new pcm. I bought pcm and Dodge dealer said it's not going the fix the surging I heard when u pulled up. PCM was flashed and installed. Engine still surging. Check engine code P1391 popped up and it's still surging. Auto Zone said they don't have a camshaft sensor and Advance didn't have one either. I assume camshaft sensor is different from the pick up coil??

[Floridajeepcherokee]

Which one is the camshaft sensor?? Is the pick up coil the camshaft sensor or is the camshaft sensor the part in the other picture circled in red???

[4.3LXJ]

No, it is the same. Camshaft position sensor is the official name. Is it still stalling?

[Floridajeepcherokee]

Ran seafoam and so far only the surging and one P1391 code

[Floridajeepcherokee]

Autozone sold me a pick up coil with 3 month warranty in February and now tell me they don't have a camshaft position...What is the part i have circled in red then above the oil filter? Can I test the pick up coil??

[4.3LXJ]

Yes it can be tested with an ohm meter. But if your engine is running, it is working. If you onm it while the engine turns over, it will make the ohm meter fluctuate up and down. To get an exact reading on it, you need an oscilloscope.

[Floridajeepcherokee]

My tach bounces and vehicle idle is surging up and down. What is the part i circled in red? I may have damaged it unplugging it when someone told me that was the cam shaft sensor and that camshaft position sensor and pickup coil are different.

[Floridajeepcherokee]

What is this part then???

[4.3LXJ]

Attaches to the block? Oil pressure sensor I think

[oderdene]

have you checked vacuum lines? Mine was surging, was a crack in vacuum line

[Floridajeepcherokee]

have you checked vacuum lines? Mine was surging, was a crack in vacuum line
I've looked but not real familiar with vacuum hoses, Wow i just found this online.
http://www.2carpros.com/questions/jeep-cherokee-1998-jeep-surging-and-backfiring talking about surging die to blown fuse on o2 heater circuit.

[Floridajeepcherokee]

https://www.youtube.com/watch?v=X3j_r4KVZcs My tach is surging like this too. I replaced IAC and TPS this year.

[Floridajeepcherokee]

Sold jeep for parts vehicle after replacing ecm/pcm and alternator. The compression check tested low. Sorry i think I have a bad taste in my mouth for Jeeps, now.