- - weird problem
11-07-2011 03:50 PM
so my jeep has been doing this for a while now but it seems like it gets worse in the winter. it mostly happens when im on my way to work because i have to be there before the sun comes up. well when i come up to the stoplight, im almost stopped and the rpms bog down really low and the jeep seems like its gonna quit but then the rpms go back to normal. i thought the tranny might have been the problem because it was causing other problems too but i got a tranny flush and the other problems stopped but this one didnt. could this be a faulty o2 sensor? or maybe a bad CPS? thanks for your advice :thumb:
11-07-2011 03:56 PM
If you haven't already I would clean your IAC. It's most likely a little dirty and sticking a bit when trying to control idle. My Jeep does it every once in awhile and I write it off as the IAC trying to catch-up when stopped, but this would be my guess.
11-07-2011 04:01 PM
is that intake air controller? or idle? lol how exactly do you clean it?
11-07-2011 04:09 PM
Idle Air Control sorry. It's on the throttle body. Pull two screws and it pops right out. Use a throttle body cleaner in a spray can to clean it up. Be sure to use a new gasket when you put it back in.
11-07-2011 04:10 PM
alright ill try that, thanks!
11-07-2011 04:14 PM
Actually try this first: buy a spray can of throttle body cleaner and with the engine running at idle spray it into the throttle body inlet. You'll have to unhook the air intake tube but I would try this before going to the trouble of removing the IAC. Follow the directions on the can. You don't have to use the whole can but just kind of intermittently spray it into the throttle body.
11-07-2011 04:39 PM
ok, that sounds a little easier lol this is just to loosen up some gunk maybe gummed up in there right? do you have to open the throttle body when spraying the cleaner in? will it mess up the motor?
11-07-2011 04:47 PM
No a throttle body cleaner won't mess up the engine. Just make sure it is throttle body cleaner. It should clean it up. There are a few write ups on here about cleaning throttle body's and IAC's you can do a search on.
11-07-2011 04:49 PM
alright, ill look into that, thanks again
11-07-2011 05:01 PM
If you type Idle Fluctuation into the search bar there is a thread with that exact title it has 43 posts. About 3 or 4 posts down on the first page Jerry Bransford has a nice little write up on it. I would post the link but I'm on my phone.
11-07-2011 06:00 PM
A few things, the MAP sensor is a vaccine supplied sensor which controls low RPM, TPS controls high IDE and erratic idle at higher speeds, IAC stumbles in 2500RPM or lower range. Most of the time its gonna be a MAP sensor if it's stalling and a gargling low idle. Check the vacuum line on the MAP sensor make sure no cracks or undone. Cleaning the IAC and TB does help. Use a tooth brush and TB cleaner should suffice.