2002 Jeep GCL - Hit and Misfire (1/6) / Rough Idle
I am Bradley Windhorst and I own a 2002 Jeep GCL above Pittsburgh, PA. I recently just bought it - listed when sold that there was a hit and miss - drove it around and didn't notice it, although we had to jump-start it each time (most likely cleared the codes then). But, anyways, code P300, P301, and P306 come up which are random misfire, misfire on cyl. 1, and misfire on cyl. 6. We replaced the cam shaft sensor, the coil system, thought it could be the computer and replaced it, but nothing has worked - problem only occurs when idling...it straightens out when you are on the gas...and it will straighten at certain times and then run fine for a while, but then just comes back a day later or so. Also, when it acts up, sometimes you can restart it and then it clears for a while...we have taken to two different places and nothing has worked - spent too much money on this to not figure it out - the fuel injectors seemed to be tampered with aka they were numbered by paint...but both shops said they seemed fine - again - it runs well for a certain time period and then it starts to rough idle and then hit and miss real badly...any ideas or suggestions???
- Must be electrical because I can drive it when it doesn't act up and it runs real well when it doesn't.
sounds exactly like mine, I also had it in 2 different shop (1 being the dealer). The dealer said that a comprssion check showed cylinder #3 with low compression. I brought it home and checked myself and confirmed that the compression seems low in #3 but still trying to determine exactly why before going any further. Very frustrating I know, i will let you know what i find please do the same if you would. I have a thread titled "compression numbers...what next". Good Luck!
Injectors were numbered so the shop knew which one was from where, when they swapped them around. A VERY logical thing to do, so no worries there.
Next would be a compression check, vacuum check and HG check. Do those and post results.
I would suggest swapping coils, plugs, injectors around, but it sounds like that has been done already.
Another thing it could be, is the injector plug itself. Had that on one rig ages ago.
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