Apologies if the answer and issue has been addressed. I've searched but haven't quite found the same set of concerns that match mine.
I have a 2004 lj with about 130xxx miles. Had somewhat of odd idle . It would fluctuate from 700 to 900 rpms when in park and when put in drive will go down to 700 rpm. With the gear in drive the rpm will surge after about 1 second off the brake and rpm will climb slightly and the jeep will increase speed and need to brake because its going to fast. Think waiting in a drive through and instead a crawl its like you giving it gas. I didn't pay attention to the rpm at those moments but if I were to guess I'd say 1100 to1200. Apply brake and drops down to 700 ish. When reverse is engaged (automatic btw) it does the same thing but the rev up and comes down revs up and comes down and the jeep reverse speed reflects veh rpm change.
Pulled the iac and cleaned though it wasn't to dirty but did not clean the housing. Later I ran about 3 4.5 oz can of throttle body clean through the iac port of the throttle body as instructed though some of the threads. I used some 6 year old non chlorinated stuff . I don't think this stuff has a shelf life.. the at idle fluctuations from 7to 900rpm seemed to have stopped sort of sometimes it stays at 900ish rpms and won't come down. Other times it will come down and doesn't fluctuate as much. The in gear rpm issues persist.
I hooked up my old my old modis. I have no codes. Looked at Iac steps . They show 62 requested and 62 steps performed with the engine off. Veh running requested steps is 0 witha flash of 1 and steps performed matches. Rpms shows 936 at idle and requested is 698 rpm but thisnin closed loop. in closed loop. Tps is showing .68 volts at idle . I didn't think to check map voltage .
Checked for vacuum leaks on the driver side of the veh and sprayed some throttle body cleaner to hear any change and nothing.
Was gonna pull the throttle body and make sure everything is really cleaned out but I'm stumped after that.
Lastly I believe this is related. In the mornings with temps in the 40 to 50s I have developed a extended crank. Key on crank for a second key off. Key on crank right over. Leaving for after work cranks right over. Work is about 9 hours. On the weekend I start my jeep later in the day when are higher and jeeps turns right over. This has started when the idle has been resting at 900 rpm
Thanks for any assistance
I have a 2004 lj with about 130xxx miles. Had somewhat of odd idle . It would fluctuate from 700 to 900 rpms when in park and when put in drive will go down to 700 rpm. With the gear in drive the rpm will surge after about 1 second off the brake and rpm will climb slightly and the jeep will increase speed and need to brake because its going to fast. Think waiting in a drive through and instead a crawl its like you giving it gas. I didn't pay attention to the rpm at those moments but if I were to guess I'd say 1100 to1200. Apply brake and drops down to 700 ish. When reverse is engaged (automatic btw) it does the same thing but the rev up and comes down revs up and comes down and the jeep reverse speed reflects veh rpm change.
Pulled the iac and cleaned though it wasn't to dirty but did not clean the housing. Later I ran about 3 4.5 oz can of throttle body clean through the iac port of the throttle body as instructed though some of the threads. I used some 6 year old non chlorinated stuff . I don't think this stuff has a shelf life.. the at idle fluctuations from 7to 900rpm seemed to have stopped sort of sometimes it stays at 900ish rpms and won't come down. Other times it will come down and doesn't fluctuate as much. The in gear rpm issues persist.
I hooked up my old my old modis. I have no codes. Looked at Iac steps . They show 62 requested and 62 steps performed with the engine off. Veh running requested steps is 0 witha flash of 1 and steps performed matches. Rpms shows 936 at idle and requested is 698 rpm but thisnin closed loop. in closed loop. Tps is showing .68 volts at idle . I didn't think to check map voltage .
Checked for vacuum leaks on the driver side of the veh and sprayed some throttle body cleaner to hear any change and nothing.
Was gonna pull the throttle body and make sure everything is really cleaned out but I'm stumped after that.
Lastly I believe this is related. In the mornings with temps in the 40 to 50s I have developed a extended crank. Key on crank for a second key off. Key on crank right over. Leaving for after work cranks right over. Work is about 9 hours. On the weekend I start my jeep later in the day when are higher and jeeps turns right over. This has started when the idle has been resting at 900 rpm
Thanks for any assistance
Last edited:
