How do I jack up the idle? M20

[henryw525i]

Almost everything on my car mechanical car has been replaced. Ever since I had the engine rebuilt it has never idled quite as smooth as it used to, especially with the air con off. With the A/C off it idles at mabye 500rpm and goes to about 600rpm with the A/C on.

Obviously I can adjust the little screw on the throttle body to jack up the idle...which works fine when the A/C is off but as soon as the A/C gets switched on it starts the idle rising to around 2000rpm.


The ICV is only 3 years old I just had the injectors cleaned and put a brand new fuel pump yesterday ($800 later) So how do I jack it up?


Thnx everyone!

[winfred]

if the throttle position switch is not being tripped the idle circuit will not turn on, id adjust the throttle to the stock spec and make sure that the tps is not only clicking but making it's connection, theres 3 wires going to it and you are looking for contenuity between the center and one of the outers, one is wide open and the other is closed

[632 Regal]

are you saying to disconnect the TPS connection, setting the idle to spec and then reconnecting the ICV? When you do the continuity is that with the engine live or off? Will the computer reset the idle rpm or is that in the adjustment?

[winfred]

nothing with the motor running, i am just talking about getting back to stock so the computer can do it's job, if it doesn't see the signal that the throttle is closed the icv is not used, i like to set the plate with the throttle body off of the car, it's really the only easy way to adjust the tps, loosen the tps screws and start backing off the throttle stop screw till the plate binds then tighten the stop screw about a half turn, then set the tps so that it clicks everytime the throttle is closed. before you adjust anything clean the crud off of the throttle body, the engine gets around 95% of it's air through the icv for idling, anything extra is uncontroled and unmeasured air and pisses it off

are you saying to disconnect the TPS connection, setting the idle to spec and then reconnecting the ICV? When you do the continuity is that with the engine live or off? Will the computer reset the idle rpm or is that in the adjustment?

[632 Regal]

nothing with the motor running, i am just talking about getting back to stock so the computer can do it's job, if it doesn't see the signal that the throttle is closed the icv is not used, i like to set the plate with the throttle body off of the car, it's really the only easy way to adjust the tps, loosen the tps screws and start backing off the throttle stop screw till the plate binds then tighten the stop screw about a half turn, then set the tps so that it clicks everytime the throttle is closed. before you adjust anything clean the crud off of the throttle body, the engine gets around 95% of it's air through the icv for idling, anything extra is uncontroled and unmeasured air and pisses it off

[winfred]

not same on v8, tps is in a fixed position

Perfect, a copy paste for my info folder, thanks gonna try it.

[632 Regal]

not same on v8, tps is in a fixed position

[winfred]

Bfh!

[henryw525i]

THANKS WINFRED...I'll go and follow the instructions