MSefi.com read only forum (Jan.15,2018)

I am running a Megasquirt v3 on my Transam with a GM TBI. The car starts fine, but will not idle. I pulled the AIC motor and it does not seem to work consistently. One time it shot the pin out. I got a new AIC and switch the coil leads, but it will not move. Is there a systematic way to test these AIC motors? Any help will greatly be appreciated.
John

I have been trying to get my IAC function to work. I have gone throught 2 IAC motor trying to understant this "simple" concept. I have a new IAC motor and to try and keep this simple I have set the start value at 160, the crank position to 0, and all of the temp table values to 0. When I turn the key on, the IAC is full retracted. The car start right up and within a minute I can get it to idle. It idles high but I expect that as the IAC is allowing maximun air in. Things are good for a while and then I hear a constant high pitch sound (which I assume is the IAC) and the car stalls out. When I turn off the car and pull the IAC motor, it is fully extended (no air flow). I have no idea why this is happening as it seems to be random. Any thoughts would be appreciate.
John

John,

Have you tried 'Always On' for the 'Idle Control/Algorithm'? You have to test it to make sure it can handle this, though. All of the stepper IAC test and troubleshooting tips are here: http://www.megamanual.com/ms2/IAC.htm#wiring

Lance.

I have a 93 trans am and my iac has the square plug. I had problems with my idle at first but I fixed it when i changed the settings, iac stepper always on and adjusted the idle steps. btw I dont know if your using tunerstudios.

Thanks for the link. I have checked my wiring and it seems to be correct which is supported by the fact that the IAC fully retracts when the key is turned on. When I start the motor, it idles for about 30 seconds before you hear the IAC motor and the engine stall. If you pull the IAC, the pin is fully extended. Occasionally Megasquirt tries to recover before the engine can stall, but it seems to be a little to late. If you pull the IAC after this type of event, the IAC pin is fully retracted. I am using tunerstudio and I have the IAC motor set to be always on, but it does not help. I have MegaSquirt v3.0 MB, so I do not see any power resistors that I can jump. Any other ideas, or ways I can test my IAC would be appreciated.
John