peterchi

1998 Grand Cherokee
Six cylinder 4.0
While driving at 30 mph the engine began to buck and near backfire. The engine idled unevenly,
but didn’t die. The “check engine” light never came on.
At the shop, my mechanic opened the hood and there was a strong smell of gas.
He pulled a spark plug and it was completely black.
He checked the sensors and found no problem with them.
No cuts were found in any of the wiring harnesses.
The connections to the ECM feel tight.
The ECM didn’t give any codes.
My mechanic thinks the ECM needs to be replaced.

Can a used ECM be reprogrammed for my Jeep?
Besides the identification number on my ECM – 56044 513AC, is there any other way to tell if
a used ECM is the right one for my Jeep?

Financially, times are a bit difficult, so I can’t replace my Jeep.

Any help is greatly appreciated.
Peter

MoToad

Match up your car at a wreckers. Gotta be the same.

dave1123

Did he check the ignition coil, cap, rotor, and wires? That's where I'd start. Pull the plugs on the PCM and look for corrosion or loose connections. Don't condemn the PCM until you check for loose plugs. Also try loosening the 2 cover screws about 1/4" and see if it runs better. If it does, replace the screws with shorter ones.

PCM=Powertrain Control Module
ECM=Electronic Counter-Measures, as in defense systems.

kibalabala

Hi members. I own a JGC2012, 3.6L 4*4 Limited. I suspect my dealer has been tampering with my vehicle whenever it goes in for service. I have a strong feeling that he removed my vehicle engine control unit and replaced it with a defective one.
Is there a way of matching an ECU with the Vehicle Identification Number so I can prove my case? Is it also possible to download a list of the serial numbers of the vehicle electrical systems through the vehicle diagnosis machine? Thanks and kind regards