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Rebuilt Computer on l997 JEEP Grand Cherokee

Hello All!
I had a rebuilt computer installed in my l997 Jeep Grand Cherokee about 3 months ago, and it worked fine until a few days ago. Is it possible the rebuilt computer was defective and, if so, would I have been able to drive 3 months without any problems? I assumed if the computer had been defective, it would have conked out much sooner.
Thanks a bunch for your insight.

What makes you feel the replacement is now faulty? Have you done proper testing to prove it is bad?

The jeep stalled, died, and was hard to start, just like it did with the old computer. All areas of the jeep had been checked by a mechanic, and no problems found. I assume it’s the rebuilt computer that is causing the latest problem, and will know tomorrow.

You don’t “rebuild” a computer like you do an engine. You repair them. After a period of time, certain computers will develop a history with certain failures. The repair people sometimes will use upgraded parts when doing the repairs so that a repaired computer is actually more reliable than a new one.

Not all companies who repair them will do the upgrades. If the repair person is not skilled at soldering on modern circuit cards, then they can cause the repaired ECM to be less reliable.

The trouble could be with the fuel delivery system, maybe the fuel pump relay. Frankly, the ECU would be pretty far down on my list of suspects. See if spraying starter fluid into the intake air helps start it up.

Afrer it was decided that I needed a new computer, I shopped around for the best price, including the Chrysler dealer, and everyone told me that there are no new computers, only rebuilt ones. Hence, the phrase “rebuilt computer”. One could always get a junk yard computer, but that wasn’t a choice I wanted. So it goes, if you need a computer, it’s going to be a rebuilt or junk yard one.
Cougar, thanks for your thoughtful reply.

You’re welcome Jeepers45. ECUs can go bad alright but until it is has been determined the problem points to it other areas are more suspect. The fuel system in this case.

If what you had for a code in the old computer was a P0351 and the PCM was replaced but the ignition coil was not, then this will continue until both are replaced.

Thanks Pete, I appreciate your thoughts, and realize that even a so called “good” mechanic can sometimes miss the potential problems. Living in a small city does not always give you access to great mechanics!
Have a great day!

Computers on cars go bad very seldom. If the choice was a rebuilt or junk yard computer, I’d pick the junk yard one. It’s likely cheaper and you’re not risking some iffy repair by someone that “rebuilt” it. Of course the warranty is likely better on the rebuilt unit.