So lately whenever I let off the accelerator by either holding down the clutch or coasting in neutral the RPMs are dropping super low, frequently as low as 500. It normally never drops below 800 or so while driving or at idle. A lot of times it fluctuates from 600-800 while coasting in neutral. Any ideas what it could be? I tried listening for any vacuum leaks under the hood with the engine running but it's so loud under there I really couldn't decipher anything.. Thanks!

 

Cammed?

 

yes, but it's been in the car since before I bought it over 50K miles ago w/ no issues until now

 

Vacuum wouldn't cause your car to idle low, but high. Check your idle control valve. And have you cleaned your injectors?

 

Hmm I'm having the same problem but dies most of the time when I press the clutch in. If I let it warm up a little then turn it off and then back on it goes to normal. Other wise I have to give it gas to keep it idling pain in the butt. I have a 98 ls1 is the iac the same as a 2000 I want the to try the 98 iac on my 2000 ta?

 

I've talked to a couple A techs and they said I should clean inside the throttle body area.. I'll probably just do the 3 step fuel induction cleaning kit that cleans out the injectors and throttle body and uses a gas tank treatment.. Where is this idle control valve? Is that the same as the IAC motor on the throttle body?

 

im having the same problem now. idk whether it could be the IAC or TPS.