onesickpantera

iTrader: (1)

I think I may have some IAC problems. First time out this year and engine was idling erratically for awhile and when I would slowly give it throttle it would hesitate, stumble and sometimes backfire. If I got it past 1800 rpm or so it would run fine. Later started idling smoother, but higher, at 800 rpm but the stumble was still there. Talked to Dennis at Innovation and he said the IAC may be sticking.

Removed the IAC and checked it to see if it would move. It does but with some resistance. How does the IAC work? I assume it should be open(plunger in) at idle and close as I give it throttle? Is there a way to test them? Should it move when I turn the key on?

Thanks

lowfunds

the iac job is to allow air around the throttle plate butterfly when the throttle is closed. it gets signal from different sensors like water temp,map sensor,etc. it is almost like a choke on a carb'd engine. it is very hard thing to move when it is out in your hand due to it is a electric motor with a worm gear to move the pintle in and out. maybe check the pintle seat because sometimes they get alittle carbon and they do not seat correctly. it is not uncommon for a iac to be bad. there is a reset program in the ddt scan tool. and there is also a iac control in the ddt to see if it moves. what it does is raise and lower the idle due to the iac opening and closing allowing more air in and out of the intake.