AS&M TB, IAC's pegged at 160
 

Hey guys, I just fired up my 396 yesterday for the first time, and it runs great. The only problem that I am encountering is that the IAC counts are pegged at 160, and dont move from there. They dipped into the 150's for a minute or two, but then back up to 160. The IAC worked fine on my stock TB when the motor was stock or on the cam/head stock bottom end setup, the counts would move accordingly, starting over 100, and going down into the 20's once the car was fully warmed up to temperature. Im not sure whats going on now, I tried the method on Shoebox's website for adjusting it, but havent had any luck. On the 350 TPI GTA I used to own, the method was the same as whats on Shoeboxs website, except at one point the IAC had to be unplugged. Can anyone shed any light on this?




Nick

Did you use the procedure on Shoebox's page to verify the condition of the IAC motor. The scanner is showing you what the PCM is telling the motor to do.... not what the IAC motor is actually doing. If the PCM tells it to open, and it doesn't actually open, the PCM will keep increasing the "counts", until it max's out at 160. Either the motor is not moving, the pintle is out too far and not retracting or the passage in the TB is plugged up.

Het Injuneer, thanks for the reply. I might just go ahead and order a new one first thing tomorrow. The passage in the throttle body isnt plugged up, its brand new with about 2 hours run time on it. When I remove a vacuum line off the intake to see if the IAC counts would move, they dropped to the 120 range. Once the vacuum line was connected, it shot right back up to 160. Adjusting the stop screw on the TB has no effect either, wether I have it idling at 1300 RPM or 700 RPM, the IAC counts are still 160. I might just go ahead and swap on the stock one to see what happens. Any other suggestions?



Nick