1FASASZ

i have a bbk 58mm throttle body, how do you set the idle scrow to where it was from the factory?

Fastbird93

If you're talking about the throttle stop screw, you don't want that set to what your stocker was from the factory. You want to set it so that the blades are correctly set for YOUR specific application. A scan tool really helps here because you can watch your IAC counts instead of just guessing.

1FASASZ

i have a scan tool, how do you do it?

turbo_Z

Set it so the TPS voltage as close as you can to .70 volts.

Fastbird93

Basically, just use the throttle stop screw to open or close the throttle blades until your IAC counts are around 40 at idle (good number). Make small changes, and after each change, shut the car off, do the IAC reset procedure, then start and let settle into idle to see where it's now at.

Lastly, adjust your TPS if necessary. Your TPS should be between .2 and .9 volts at idle. The "sweet spot" that most have found is in the .55-.65 area.

1FASASZ

how do i do this?

shoebox

How to

1FASASZ

i cant get my iac count anywhere close to 40, it likes to stay arount 150 no matter what i do. and my tps voltage is about 1.1 what should i do

matt65

I had to slightly slot the mounting screws to allow adjustment in mounting. This allows for sensor rotation.

Injuneer

With what is probably a fairly aggressive cam, focus first on the TPS voltage. When the voltage is above 1.0 at idle it throws everything off. In fact, you should be getting a code for high TPS voltage.

How low you can get the IAC counts will depend on the idle speed that was programmed in the PCM, and the aggressiveness of the cam. First get the TPS voltage where it belongs. But that may be difficult, because as you close down the blades, there's no room for the IAC motor to open up to hold the idle speed, and it may stall.

Is it possible the IAC motor is not working, or the passages are plugged up? Is it actually reading "160" which would indicate the PCM has max'd out the adjustment and the motor may not be responding?

1FASASZ

thanks ill give that a try

96capricemgr

http://members.***.net/chipsbyal/page/idle/index.html
BBK only needs the hole drilled you will not need to make the plug he does.