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View Full Version : 96 ZJ keeps Killing Computer



Metlic53
07-03-2017, 07:28 PM
I have a 96 grand Cherokee with the 4.0.
I bought it not running and am having trouble with the computer. I put a new computer in and will run at an IDLE but when I put it in gear and drive it a few feet it will just die. I lose all gauges and nothing works until I replace the computer again. All it will do it crank and crank. I took the computer out of my XJ and it did the same thing. It kills the computer, tried putting the computer back in the XJ and I get nothing, no gauges and just cranks and cranks. Not sure if its transmission related but the guy I bought it from had just replaced the transmission and it wouldn't run after that. Are they any tranny wires that could be crossed or screwed up that would keep frying a ECM like that?

4.3LXJ
07-03-2017, 07:31 PM
There is a screw that is too long on the ZJ, and it kills the ECM. All you have to do is shorten it. Not sure which one, but that is the skinny

Metlic53
07-03-2017, 07:43 PM
There is a screw that is too long on the ZJ, and it kills the ECM. All you have to do is shorten it. Not sure which one, but that is the skinny

a screw on the ECM itself?

Metlic53
07-03-2017, 08:02 PM
seems kinda strange that ive changed 4 ecms out and all of that get fried within a few minutes of running.

4.3LXJ
07-03-2017, 08:36 PM
Yes, just a screw. It is too long and contacts the board, or back of the case and causes a short which fries the board. The solution is simple. Shorter screw.

drakan1908
07-04-2017, 06:00 AM
Check the wiring that goes to the tranny from computer. When they changed the tranny they could have pinched or cut a wire and it is shorting out.

Sent from a van down by the river