Hey guys I've always had issues with a rough idle upon a cold start and lately ive been trying to track it down and fix it. after a couple seconds it will rev up then smooth out. lately it seems to have been getting worse so i have started replacing sensors due to the age and mileage (400k).
I've replaced the TPS, IAC, MAP, and both Cam, and Crank Position Sensor. After all of these sensors I have disconnected the battery and let it discharge and hoped it would relearn and solve the issue but it has not. It's a fresh rebuilt 4.0 now and an entirely new ignition system but still having these issues. The only code i have is for a non functioning speedometer and it has a miss every couple cycles of the engine when idling.
Its gotten to the point I thought this was normal for the 4.0 engines until I've seen videos of xjs starting up and running like a normal vehicle should (who would've guessed)
Where else should I be looking and what else should I be testing? thank you guys in advance you are great help and I greatly appreciate it!
I've replaced the TPS, IAC, MAP, and both Cam, and Crank Position Sensor. After all of these sensors I have disconnected the battery and let it discharge and hoped it would relearn and solve the issue but it has not. It's a fresh rebuilt 4.0 now and an entirely new ignition system but still having these issues. The only code i have is for a non functioning speedometer and it has a miss every couple cycles of the engine when idling.
Its gotten to the point I thought this was normal for the 4.0 engines until I've seen videos of xjs starting up and running like a normal vehicle should (who would've guessed)
Where else should I be looking and what else should I be testing? thank you guys in advance you are great help and I greatly appreciate it!