00Pajeepcherokee

My 00 just started doing this today. Starts and runs fine. Right off of idle it will jump up in rpms after letting off of the throttle. Also anytime I let off of the throttle it does this. Just touching the gas, it will jump up to 1800-2000 rpms an stay there for like 3-4 seconds. Its not cool and even dangerous. Any ideas. I unplugged an plugged all the sensors around the tb back in. I think Its sensor related but I don't have a clue. No cel either. I recently did the 784 injector swap but its run flawlessly for 3 weeks now, no issues till now. My pcv valve is busted on the back of the valve cover but again its run fine for 3 weeks like this also. Ideas? Thanks guys

Ender

Mine did the same thing, idle jump @ start up, put in a new TPS and fixed the problem...
Good luck..

freegdr

i would check for codes even if no light is on sound like maybe iac is dirty or stuck /

00Pajeepcherokee

Where is the iac and what does it look like exactly?

I unplugged a sensor on the passenger side of the tb closest to the fuel rail and that fixed it. So wth does that mean?

Fanmanj

To me, it sounds as if the iac is having trouble compensating for the vacuum leak caused by the broken Pcv valve. I would start there,By replacing that broken Pcv. and also as others have suggested clean your iac valve and it's port.

Five zero eight

I had this problem, I took a whole tb assevly off a 97 at a junkyard and put it on and fixed it, it was the iac that was ****ed.

freegdr

fix the vacuum leak firstthen i would check for codes first,the iac is were the red arrow is

00Pajeepcherokee

Thanks. I need to fix the pcv thing. I guess the only place to get one is from a Dodge dealership. Which sensor do I have unplugged and why did it take away my revving issue?

freegdr

ive heard napa sells the thing also and with out a pic of what you have unplugged nobody can tell you

00Pajeepcherokee

I'll try to get a pic here soon

00Pajeepcherokee

This is what I have unplugged

freegdr

thats the iac remove the two torx bolts and clean the point of it and the hole it goes in do not attempt to move the mechanism at all just clean it with carb cleaner remove the o ring b4 cleaning and see if it helps

00Pajeepcherokee

OK cool I'll give it a try! Thanks

freegdr

whats with the silicone around the throttle body how longs that been there

A_Jeepr

Clean the throttle body (TB). The IAC (idle air control valve) isn't always the problem, most of the time the port in the TB is clogging up. Take some throttle body cleaner and an old toothbrush.... or your signifigant other's (just remember to buy new brush ) and go to town, you don't need to remove the TB to do this. *However do not use carb cleaner it will damage the finish and cause it to gum up even worse.

if doing the above don't work or help it would be the IAC. Remember, cheaper fix first.