hello everyone. i was very impressed with the assistance you gave a member and since i have an aging pontiac grand am that is becoming more than i can handle i thought i should sign up and see if anyone has any ideas. grand am has 90,000 miles on it. ive just finished the tuneup and oxygen sensor was replaced a couple of years ago. ive replaced the iac 3 times in as many years but problem is cant get it smogged due to high idle speed. on this model it is not adjustable and iac doesnt do anything when in park. any ideas on what i should check.

Check for a vacuum leak between the throttle body and around the intake manifold. Easier to spray carb/choke cleaner around gasket mating areas while engine is running. If the idle changes while spraying, you found a leak. Check all vac lines also.

thanks car is 60 miles away will let you know what i find out

i know it has a leak in the heater control lines. would that affect the engine lines

Welcome to the forum.

thanks
my apologies to the board i dont use them much and am unfamiliar with how they work. i should not have posted in this section . i will be more attentive about screens next time and thanks for the help.

if your problem is vacuum leak in your heater control that will affect the engine. find the line and cap the engine side and see if it changes

thanks mike1995

well i found line into cabin and capped it off and idle dropped so i fixed the heater vacuum line. thanks! one last question if i may where is the tachometer lead on this car if it has one. need to make sure its within specs for smog. thanks again.

thanks to you also jwfirebird

All we know is you have an aging Grand Am. If we are to answer questions specific to your vehicle we need to know year, model, engine, etc.