new computer

[hulk]

Hey have any of you guys replaced your computer? And if so any advice? like did you only stick too the stealership? or did you have any aftermarket succes. i have a 95 XJ that keeps shutting off when i hit bumps. yeah its sort of weird. any ways i have replaced everything at least 3 times or more. the CPS- relays- fuel pump-ignition sitch-all connectors- and so forth. i have sent my computer in twice to be rebuilt. the company acknowledges a problem- but the problem never gets fixed. So i am done with it. WHERE SHOULD I BUY A NEW COMPUTER&HARNESS? SAVE ME BEFORE I GO TO A ZJ. THANKS IN ADVANCE FOR YOUR HELP.

[langer1]

I doubt the computer is your problem, a rebuilt computer is not even the same one. It would be hard to beleve you got two of them with the same problem.
Do you have a anti-thieft system?

[UNCC_99XJ]

I also doubt the computer is the issue, sounds like a loose wire somewhere. Have you started tracing wires at all?

[AJPulley]

You know, it could be the computer. My 87's will not de-energize the EGR solenoid. Really. I finally troubleshot it until I tested the correct wire comming right out of the computer. I don't understand it, but it still runs fine. So, I capped the vacume supply to the solenoid and since I had a new cat installed four years ago, I still pass emisions, in MA, with flying colors. Picces me off too since I spent a small chunk for a new EGR. So, just maybe it is.

[CheapXJ]

Originally Posted by hulk

SAVE ME BEFORE I GO TO A ZJ.

you want something less reliable?

go to a junkyard and grab another engine harness.

there will be a sticker on your comp w/ a number on it, match that nubmer if you can. if not, just make sure that you get the comp from another 91-95 w/ the same tranny.

[hulk]

Well its pretty odd guys. i have traced the wires, and did the old shake it till it almost breaks. but of course it wont respond in my driveway, but on the freeway, oh yeah not a problem. it is pretty odd. the first time my computer was rebuilt, when it would stall, it would shut off, but the ignition lights would stay on. like check engine, oil, and tempature, you know the lights you have right before you start your jeep. now when my xj stalls, everything goes dead, no power at all. then like both instances, if i wait about 30 secs the SOB fires right up, no problem. then when i check the codes, it tells me the old 55. HOW CAN THAT POSSIBLY BE.

[langer1]

There are a few electrical things the computer don't monitor.
If you had a failing ignition switch, that would not cause a code.
And explain why everything goes off, a bad relay in the anti-thieft could also cause it.

[old_man]

I have seen a bad battery cause what you describe. When it got bumped a couple of plates would short out. This is actually not that uncommon if the battery isn't tied down. Make sure the ground from the head to the firewall is intact. Around here a ECU from pull-n-save runs around $30.

[langer1]

Originally Posted by old_man

I have seen a bad battery cause what you describe. When it got bumped a couple of plates would short out. This is actually not that uncommon if the battery isn't tied down. Make sure the ground from the head to the firewall is intact. Around here a ECU from pull-n-save runs around $30.

Wouldn't that cause a code 12 "battery disconnect" code?