Chosen Solution
I had posted a problem about this before…. and proclaimed my victory after a tune up…….. then back to the same issues the next day. SO, i have replaced the idle position sensor. Cleaned the throttle body but not off the intake clean, but cleaned it. also the tune up mentioned above. and no codes, computer isn’t throwing back any codes not sure if computer keeps track of this. When first started for the day,it’s ok….. idles a bit high and settles down once warmed up a bit…… so if i keep driving it around and not turn it off it seems to be ok for the most part….. sometimes once it gets up to normal operating temp. it will idle a bit low. SO i turn it off and start it right back up last week at mechanic’s shop and it works just fine of course. most of the time if i go out and get back in it to go home etc. it either won’t start without pushing on the gas, reving it a bit, or kinda driving with both feet. When this thing acts up you can put it in drive and it idles so low it will learch forward bit at a time. So if anyone has any ideas, let me know……. I would test for a vacuum leak but don’t know how to do that. Could it be a intermittent problem with the crank position sensor? I had that go bad before but usually the jeep just won’t start or runs messed up. I also can’t understand the odd sometimes working behavior……. and no consistent problem to find a solution. this isn’t a 1986 jeep with a carb or something, so not sure whats going on, this sort of can’t figure it out stuff should be behind us with OBDII etc? i dont intend to go on any sort of rant but this has been a problem for a long enough now. ALMOST FORGOT: 2000 jeep cherokee 4.0L ( with the coil packs not regular ignition plug wires etc) ….. its a limited XJ trim, that shouldn’t matter but thats what it is.
What it sounds like to me is you have a vacuum leak. Idle bogging under load is a pretty common sign of a vac leak. Easy way to test for a vac leak without any gauges is to spray break parts cleaner or carb cleaner all over the motor while its running and when your idle jumps thats the area where your vac leak is at. If that doesn’t work I would clean the sensor of your afm with afm cleaner NOT brake parts cleaner! Start with those two things and im 99% positive you will find your culprit and fix it! Will
Had exact same problem. ODBII indicated check engine light was owing to TPS (Throttle Position Sensor). TPS checked out okay. However problem eventually traced to TPS connector plug. Unplugged, WD40 applied to male/female connections, connection worked by connecting/disconnecting, left overnight. No more stuttering or hesitation in lower gears at 1250 - 1500 rpm. Idles like new. Advise checking electrical connections especially if vehicle lives outside in damp climate.
Same problem mine was idle air control valve and tps 229000 miles 4.0 l
Location Chicago: I have a 2001 Cherokee and have the same issues with the idle control. This problem has developed over the last 5 years. A few things I have figured out after numerous attempts to fix the issue. It does not seem to matter how often I replace the sensor or test the functions, the symptoms continue to occur in different times of the year. These symptoms seems to occur seasonal or with changes in the weather. I can go months without a single problem and one day…. Dam… it’s not working again. It continues to not function properly for a week or so and suddenly it works for another few months. I know we are gong into our snow season and 3 days ago it started having its issues. I can’t warm up my car in the cold without sitting in it and manually keeping the idle up other wise the idle immediately drops to 0 and engine dies. My idle also has done the opposite and reached almost 2000 rpm or 2,500 rpm and I actually have to press on the brake so it does not move forward. It is scary to hear the engine reach such High levels because I feel I can’t control it. I can’t use my remote starter because of these problems. Sometimes when I step on the accelerator and give it some gas in high idle it may correct itself, but most likely it does nothing. Extra acceleration does not correct in low idle. People have mentioned that I might have a vacuum leak, but when I tell them that it comes and goes 2 times a year, they look at me in a bewildered way. I have not done a vacuum leak because the symptoms are not continuous. If I had a vacuum leak it would have this problem all the time and it doesn’t. So, I concluded over several attempts to fix this issue myself and with professional mechanics replacing parts and the symptoms still Come and go twice a year. Seasonal changes must play a role in how my jeep functions. Any advice will be greatly appreciated or I am just crazy. ?
