My idle is currently set at 750...I think that is a bit low seeing that the car will only start on the first try when it's warm; the cam is a 224/218 comp grind, and the car's an auto with a 3200rpm stall. I've played with the throttle body blade screw and gotten my IAC counts tuned in every time I've raised the idle (trying to find the right rpm a little at a time). I think my next jump will be to 850.

Here's my question: The car was previously tuned by Ed Wright...my throttle body blade was never drilled out, nor was my throttle body blade screw ever turned from the stock setting. I never autotapped it with that tuning to see what the IAC counts were, but I'm betting they were pretty high. The car always started right up, and only ever stalled shifting from neutral to reverse once (shortly after the H/C install...I assume the computer just wasn't used to everything yet). I'm pretty sure Ed had my idle set at 850 (my tach is anywhere from 250-400rpm off!), but shouldn't the high (100+) IAC counts given me problems?

Question 2: do you think raising my idle to 850 and adjusting my throttle body screw to dial in the IAC counts will solve my cold idle problems? Is there anything else I should be adjusting to set my idle?

Thanks for your input...I know the post is kinda long.

 

The first thing you need to do is get Autotapped and quit guessing about your IAC counts.

Don't open that throttle blade up too much. The PCM doesn't like it past a certain point. Personally, I'd close the TB back to stock and get my IAC counts down below 30 (engine FULLY warmed) by drilling the TB blade hole bigger. Either that or I'd raise the IAC park position with LS1Edit.

 

Colonel, thanks for the response. I've autotapped it everytime I've opened the throttle body up, so my IAC counts are damn near perfect (right around 30 with no accessories on). I'll try closing the throttle body up (I've only opened it about a turn and a half), but if that is going to cause additional problems, I might as well use the throttle body hole method.

As for raising the IAC park position, how high should I go? Is there a value that is "too high". Thanks again for the input.

 

TTT....anyone know how high is too high for the IAC park position setting?

 

Too high and the engine won't return to idle quick enough. It'll float above idle and then settle down.