Q: my99 3.1 gm idles up and down replaced the iac and egr what gives then dies but driving its ok

asked by on January 10, 2018

imy car idles up and down then stalls changed the iac and egr still the same and also cleaned any clogs and replaced the pvc hoses still the same idles up and down runs good when driving and stalls at lights. have to keep foot on brake and gas to keep running, what the hell.

My car has 213000 miles.
My car has an automatic transmission.

You most likely have a intake vacuum leak. You should have the computer scanned first to make sure you do not have a TPS problem or other sensor issue. Pinch off the vacuum line to the brake booster to see if it idles better indicating booster is leaking also. If you need more help locating vacuum leaks then consult a mechanic like one from YourMechanic.

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