Setting Idle: Which Screw On This Tb Is Correct One To Use?

from6to8 said:

I have always set my idle using the throttle body set screw on the outside throttle wheel thing as I have seen it adjusted there back when I was pretty much a novice. I will provide 2 pics of the different screws on the professional products tb and also a link to where they talk about adjusting it via that same screw I was using. I'm sure there was someone on a site who said I was setting it with the wrong screw. Last time I set idle and tried to use the other screw in indented hole, the only direction I could go would raise the idle. Going the other direction the screw was tight. NOt sure if I was supposed to keep trying to turn or not so I tried adjusting with the one I always used first then the indented screw. Well that didnt work either. Just trying to verify if indeed the idle can be set or not set with the screw I was using all along.

Here's the link to that thread about the 94/95 tb even though mine is a professional products aftermarket:

http://www.muscularmustangs.com/idlereset.php

Click to expand...

you should never touch the plenum adjust screw unless the tip of the screw has
crushed down a hint. if you have idle trouble its probably tps/iac related. the flap in there has to stay where ford had set it unless a you have special mods. period. if you adjust it you screw with the tps idle voltage and the amount of air getting past the flap. not a good idea

I have a question as I am having issues right now with my setup when the car is warm. Basically I followed the same procedure linked above to set my Base Idle which for my cam I have it at 900 RPM's. I have brand new IAC/TPS and are tested perfect. Now when I first start my car and its COLD IDLE is perfect but once I take it out for a short drive and the car is at WARM IDLE the computer jacks it up to 2000-2100 RPM's at first I thought gasket/vacuum leak and inspected everything to find none. But then I unplugged the IAC and the car drops back down perfectly to my base idle of 900 RPM's like I set it. So after you set the Base Idle should let the car sit without touching the throttle and Idle until it reaches the operating temp (180-190 degrees) before driving it to get it to learn the correct WARM IDLE as well? Any input would be GREATLY appreciated with this

Also should the car be at 180-190 degree's operating temperature before even attempting to set the base idle? I dont see it stated in any of these articles on the net about setting the base idle but maybe that is my problem as I am setting it from a cold motor?

I would have the engine at operating temps as there are other parameters the computer uses to maintain idle when cold.

This is probably the best reset procedure.