Jeep 4.0 High Idle

[@robertfinchii5605]

I have a 1999 Jeep Cherokee 4.0L / straight 6Cy that has a mind of its own when it comes to (Idling ) sometimes good then , it goes (BAD) really bad that check engine light comes on !! ( what’s my best solution to fix Problem) ??

[@PatsCarGarage]

That sounds very similar to what I had. I've made a follow up video to this one if you want to check it out, but basically, the ECU had a bad ground, so a lot of intermittent issues would pop up, including the idle. Running new grounds and cleaning up all the connections fixed everything.

[@westcoast3595]

US here. Costs as much or more for quality stuff

[@fredflintstone6903]

very helpful thank you

[@ibberman]

How did you adjust it ? The screw on my 93 does not have a slot in it for a screwdriver.

[@PatsCarGarage]

Good, don't touch it.

[@MrTM-fg6zn]

Mine had a vacuum hose pop off the intake.

[@brandonloy2679]

My Jeep isles at 1000 rpms and I’ve adjusted the screw all the way down and changed all sensors what could it be

[@PatsCarGarage]

Does your jeep's engine occasionally get seemingly unrelated problems? Like a code for bad O2 sensor?

[@brandonloy2679]

Pat's Car Garage idk I’ve never been able to find an obd 1 scanner and when I turn the key to do a manual read nothing shows up

[@PatsCarGarage]

@@brandonloy2679 If you did have other issues I would have said to check the ECM ground. It's probably still worth a shot. The factory ground splices 4 wires into a thicker one (3 ECM grounds and the O2 sensor ground) with a janky heatshrink splice. I replaced the crappy heatshrink splice with an 8 gauge butt connector and crimped it with a crimping tool. I also cleaned up all the main ground connections (at the ignition coil stud and finally the battery itself) and it cured the remaining intermittent high idle I had, despite the fixes I mentionned in the video.

[@jeep146]

Did you ever fix the high idle problem?

[@PatsCarGarage]

@@jeep146 yes, it was a bad ECM ground

[@Yttikymmug]

yeah you showing fingers turning instead of tools is not helpful at all.

[@PatsCarGarage]

same as you, typing out pointless, unhelpful comments instead of asking questions. Care to try again?

[@michaelfulton6662]

You talking to much