Some times when I start my 89 Cherokee 4.0 the engine will rev up to around 3000 rpm and wont come down unless I shut down the car and restart it. In some cases I have had to turn off the car and start it a couple of times to get the idle down. This also sometimes happens while the car is running, meaning The car starts just fine then I will notice while at a light or something that the idle is up to high, around 3000 rpm.
If any knows what is going on here or has experienced the same thing, a cure for this problem would be appreciated. Thanks
5.9 litre, stock. 89 XJ with 5 inch lift, roof rack and 31X10.5`s on 589`s. 76 Wagoneer with 401,edelbrock,MSD,Header and B&M auto shifter.
are you sure the choke just isn't sticking??
make sure the petals and lnes aren't catching on anything
Jeep: '88 YJ Laredo I6, Kenwood Deck, Amp and 6x9's, 10" pioneer sub, 2.5" Skyjacker Kit with a 1" body and new front shackles, 32" Mud Kings on 8" Desert Crawlers, CJ style replacement mirrors, ditched the trackbars and the endcaps
I have had the same problem with my 1990 4.0L Comanche. Changing the EGR valve reduced the problem alot, but it still happens occasionally, especially when I put low grade fuel into it - it really appreciates a tank of premium, although mid-grade works fine too.
It is most likely an issue connected with vacuum lines and/or emmission control components. Let us know what you come up with - this is a VERY common problem.
I had a motor with a bad tempature sensor that sent the idle up to over 3000 rpm. It took three different mechanics to figure out what was wrong. I can't promise it'll fix your problem but it fixed mine.
i learned about this sensor bs the hard way.i wouldn't just go replacing sensors on someones advice.it get's rather expensive if it's not the fix.it sounds like a throttle position sensor...but don't take my word for it. spend the money and have a diagnostic done.it will save much heartache and money.btw, the 4 cylinder uses the same tps as the 4.0.it is a problem child.
who ever said putting a spool in a daily driver was a bad idea was just jealous he had not tried it first...