Jeep Grand Cherokee 2000 4.7
I am trying to help my electrician figure out what could be the issue with the engine’s unstable idle speed and then stalling when warm eventually.
Long story short, I took car to the electrician because the car didn’t want to start for most of the time (when the engine was warm mostly). I needed usually to remove and put back back battery cables, then it would reset and start straight away. So the electrician had an idea. He added his custom-made module, which did reset everytime something in the ECU and then the engine could start easily. Then after a few days, a sudden issue with idle arose. (even when we removed that module it didn’t fix the idle issue)
When the engine is cold idle starts to go up and down (by a fraction) and then when the engine reaches operating temperature and when I stop (either in the drive mode or parking) the engine just dies. Not all the time, but I would say 80%.
When the car is in parking and the gas is pressed a bit to keep (rpm) up, the engine won’t die.
Following things have been changed so far (some things twice to be 100% sure it is not the sensor)
-camshaft sensor (twice)
-crankshaft sensor (twice)
-tried another ECU (we thought that this was the issue for starting and idle but it wasn’t)
-idle air control valve (electrician cleaned that, but we didn’t replace to a new one)
Following things that we could try:
We are thinking to replace wires to the camshaft and crankshaft sensor, perhaps that could be the issue?
Not sure but perhaps MAF (mass airflow) sensor should be replaced as well?
Also thinking to replace the ‘idle air control valve’ with a brand new one.
What are your ideas guys, what should we do next? I am not worried that much about the engine starting issue (since the module can fix that) but the idle issues are the biggest issues right now.
Thank you for your time!