My sister called me today and said that her jeep, which is a 99 cherokee se, runs fine when driving it but when she comes to a light or parks it the rpms race up and then it almost stalls. She has to give it gas so it doesnt stall. It isnt throwing any check engine lights as of now. Any ideas of what could be causing this?
Thanks

 

Sounds like you should just give her my #
Sorry
I had to
But how long has she gone sense she had a tune up? Sense there's no code I would start there. Other thoughts just thoughts is throttle control sen, 02 sen, map sen just thoughts but for those her light should be on.

 

Have a look at the iac (idle air control) , clean the throttle body, see if that helps. Could also be a vac leak or tune-up as the op suggested

 

sorry no can do on that one. haha

but i just tuned it up about 4 months ago. and im stumped on the why it isnt throwing a code.

 

Sounds like a vacuum leak to me, and that wouldn't normally set a CEL. JMO
Dan

 

Ok thanks. Im heading home tomorrow and ill check for any vacuum leaks and ill tune it up again.

 

I replaced the IAC valve which helped with the high idle but then it started missing so i replaced the cap/rotor, wires, and plugs and it was still missing. So i replaced the throttle positioning sensor and it seems fine now. Thanks for the help everyone.

 

Well I'm glad you've got it running up to par again.

Dan

 

Hi I'm having the same problem described above: engine idle will race pretty high when first startup and also when in Neutral and Park. In drive it's pretty normal speed but it will dip low and sorta seem like it's gonna stall out when at low speeds.

Ideas???

 

Idle air control on throttle body. Try cleaning it with throttle body cleaner spray. Check all ground wires too.

 

Sounds like TPS to me