88droptopgt

"with IAC disconnected to 650 rpms"


HUH? disconnect it to 650???

Joel5.0

With IAC disconnected set base idle to 650 rpms......you have to take the Idle Air Control (IAC) out of the setup procedure.......

...and adjust idle via the throttle stop screw (under the throttle body)........

88droptopgt

Stupid question, how do I know where 650 is at?

Joel5.0

Instrument panel tachometer, a line up the middle mark between 0 and 1 .....although having one of these will make it a more accurate setting.

88droptopgt

Sorry, I am lost here, but the car wont run with the IAC not hooked up, how do I see 650 then?

AdderMk2

you need to get it warm first... then it will idle at 650

88droptopgt

once the car is warm, it will run even when IAC is unplugged?

AdderMk2

mine does.... my IAC does some whacky stuff, but im too lazy to replace it right now.. so when it acts really bad, i just unplug it.

Most race cars dont even have IAC valves

Joel5.0

Raise the idle via the stop screw first until it idles w/out the IAC....then set it to 650 rpms....and yep...as Adder said, engine has to be to op temp.

shaners90lxhatch

Your engine should stall if you just disconnect it. The proper way to reset your base idle (besides getting it to full op temp) is to rev the engine slightly, unplug the IAC and then slowly return it to idle. It should idle at about 550RPM. You should idle at 800RPM with the IAC plugged in and the IAC duty cycle should be around 30% but you won't be able to check that. You shouldn't have to adjust the throttle stop. Odds are something else is wrong if you do. If you idle high, you may have a vacuum leak. Advancing your timing will up your idle speed as well.