Hi guy I just bought a 94 teg ls. The previous owner rebuilt the ls engine back to stock, it runs good and everything but the idleling flunctuates between 500-1500 rpm. Sorry I dont have the helms yet I bought the car yesterday. How do I go about fixing this? Thanx guys

 

You either have a vacuum leak somewhere or the IACV is dirty

 

Check the Idle valve located under the Throttle Body. Also make sure that your cooling system has been bled of any excess air. If after both of these items have been cleared and the problem still persists check the IAC on the back of the intake. After that if you still have the problem then there is a vaccum leak somewhere. Hope this helps.

 

Yup this helps alot thanx for you help

 

unplug the IACV (electrical connector) and see if the car turns off, if it does then you need a new IACV otherwise the car should just idle very low (perhaps under 200rpm) Now if it does do that then check the cleanliness of the filter in the IACV, if that is clean then i suggest checking the FITV under the IACV (Clean the FITV) If the problem persists then go check all the vacuum lines and feel for leaks etc.

If all that fails then you can always try to reset the idle by adjustiung the idle screw on the Throttle Body.

 

When you do clean the IACV I recommend using compressed air with some good old carb cleaner does the job really well. Don't forget to take off the rubber rings before spraying inside the two holes because it will swell up.

 

any update on what the problem was?

 

How to you go about bleeding your coolant system? because I recently put in a new radiator and I think there is lots of air in the system.

 

fix it?

 

it should be a vacuum leak most likely.