I started up my 91 Formula 305 last night (first time after putting TPI back on). I jumped A&B on the ALDL, waited 30 seconds, and unplugged the IAC wires so that I could adjust the idle. The car ran fine except that I had to have my foot on the gas pedal to get the car to "idle". If I let off the gas, it just died. I have not adjusted the TPS or the IAC. I did not mess with the idle screw because it just wouldn't hold an idle.

My question is how tight do I screw in the IAC before I start messing with the idle screw on the TB?

Just a comment: I did not have the air filter hooked up, and it was the first time I had run it with the air foil and the power and amp pulleys. I am guessing that those three things were the cause of the incredible throttle response.

 

There's no torque spec or other indicator?

 

if you are putting your org. tpi back on your car then you shouldnt have to adjust the IAC.But if you have too thenyour right about the idle screw. I would do this once to get it to idle then once it is up to temp recheck and adjust if ness. i tightnened mine just enough so that the gasket sealed. remember, its only plastic so wrenching on it like its a lugnut spells disater.

 

OK, that's just what I needed. I took the IAC out of it's housing because I was bypassing the TB and I cut off the nipples, filled the holes, and sanded it flush. Needless to say, it was easier with the IAC out.

I'll just tighten the IAC until I get an idle. I also need to adjust the TPS, but I need an idle before I can do that.

 

you cant tightnen the IAC until you get an idle. tighten it up until its tight with the engine off. then plug it back togehter and start car. if the car wont idle then turn the screw until you are comfotable with how it idles. make sure you do this when the engine is up to temp.