So the car in my sig has a hanging idle and I couldnt find any vacuum leaks so I bought a new IAC and cannot get it to idle correctly. Also, this IAC has a metal pintle on the end and not a rubber one like the factory. This one is also adjustable and you can unscrew the pintle.

So what is the proper procedure to adjust the throttle blade and what temperature does the engine have to be at? I played with the throttle blade adjustment thinking this was the issue. I now have it warm idle IAC counts at 45. The only problem is, when I start it up cold and drive it, it wants to stall.

Do I need to reset the tps and iac and then start it up and let it idle until warm and then turn a/c and let it idle? I read this somewhere.

 

The throttle stop screw, you only want to prevent the
blade from binding in the throat under vacuum. I'd back
it out, let the blade snap shut, and then turn it in until
you just feel / see the blade move.

Your cold stall could be not enough commanded air,
or it could be over-enrichment if it yo-yos and then
stalls out. Log the actual dynamic airflow from a cold
start, and the ECT, and then look at the desired air
table values in comparison.

There's a field for closed loop idle RPM enable ECT.
Below that you're running off airflow target alone,
via the IAC position vs airflow table.

But it would not be surprising that if the IAC is
physically different, that table no longer represents
that aspect faithfully. I think I'd look for an OE-type
piece (you could maybe borrow one) just to see.

 

Thanks, I actually am just using a Aeroforce gauge to watch IAC counts. The car idled great before, no stalling. I will try my stock IAC and see if this helps. Do I have to reset my tps and IAC when I put the old IAC back in?

 

So I put the old IAC back in, have the iac counts around 45 at hot idle. Are you supposed to reset the IAC and TPS each time you move the throttle blade screw? Also, the car smells alot more now like its rich, do I need to bring the car to a tuner to fix the issue or can I fix it by just monitoring the IAC counts?

 

So do I just need to get my iac counts back to normal(20 to 50)? Is this while my temperature is at 180 or 220? I read somewhere you can turn off the fans so it will reach this temperature. My tps voltage is like .47 to 4.6 or so, this is off the top of my head. I noticed the car smells real bad, like its rich. This is only during warm up.