Vent Control Solenoid/Evap Solenoid

[Klaatu55]

Where is the vent control solenoid located in my 1999 4.0 Cherokee and is the evap. solenoid a separate part or are they the same thing. I know about the one in the engine compartment next to the evap pump. Im looking for the one that when held closed prevents the fuel tank from filling at a regular rate. Articles that I read make it sound like two separate components. - Ii pulled both vacuum hoses off of the solenoid in the engine compartment. i went to get gas, Pump still kept cutting off. Must be another solenoid somewhere, thought i traced all three hose coming out of charcoal canister - Thanks

[bluedragon436]

A little late maybe.. But the only valve I know of is the purge valve solenoid which is the one under the hood... I will say if you decide to replace that one, to see if it helps your issue... order it from Rock Auto... not only because they are a vendor here... but because it's like $25 roughly, compared to like $40+ at local auto parts store... even with the shipping it was way cheaper than I could find locally... As far as the gas pump kicking off.. is it doing it like as soon as you start filling, or towards the end of the tank being almost full (just earlier than it should, like before it is really full)??

[Klaatu55]

As a follow up to two problems that have plagued me for over a year in the case of low fuel pressure more than two years.

Few years ago I was having trouble starting, had to do the double key on thing to get started.

I checked fuel pressure at the fuel rail and found that the fuel pressure dropped almost immediately upon shutting motor down. I suspected a bad check valve in fuel pump. I changed the entire pump assembly.

While I had the old pump out I thoroughly washed,rinsed,and allowed the fuel tank to dry.

I put everything back together and I found I still had the same problem.
I took defective pump back for exchange (which was pain free) installed a new pump (different brand).Same problem.

Thinking it must be a leak somewhere in line between pump and fuel rail. Also put in fuel injector mod.

Now I also had a problem with gassing up, gas station pump would stop every couple of seconds. And threw evap. system code, I worked with these two conditions for over a year trying to trouble shoot leak.

Finally bit the bullet and bought a brand new pump.

After I removed the pump I reached into fuel tank and found what I believe to be a combination rollover valve and vent valve The mechanism had come loose (ping pong ball with a spring in a cage) II guess had come loose with I was washing tank. t was now seating right. Put pump back in. Now every thing is working as designed. Pressure runs at approximately 50 psi when motor running Key Off the pressure drops to 14-30, but still holds enough fuel at rail so that so you get instant an start. Hope this helps someone. Time for me to screw something else up.Thanks everyone for your help,.

[bluedragon436]

Nice.. Glad it all seems to be worked out for you now.. I think I'm going to have to bite the bullet here shortly and replace my fuel pump. I haven't checked the fuel pressure @ the rail yet, will do that here shortly to make sure what I think is the issue is actually the/an issue.. Usually if I haven't driven my XJ in a few days, I'll have to either let her turn over for a few before it'll fire up, or I have found that if I turn the key on, to where the pump primes, then turn it off, then back on again and start it, it'll start pretty much like normal.. So I'm assuming that the fuel is draining completely back down into the tank, or at least a good bit of the way back to the tank.. Like I said, going to check the pressure @ the rail when it is running, as well as when I cut it off, then again after an hour or so... then leave it alone until the next day and then check and see where it is sitting after being left alone for roughly 24hrs...