1G BISS Screw

[mitsuowner1991]

If the biss screw is all the way in does that make my idle high?? If i back it out will the idle go down?

 

[steve]

No, screwing the BISS in closes the air bypass and should lower the the idle speed once the ECU can no longer compensate using the ISC/IAC and timing.

Unless you have told the ECU that your adjusting the Basic Idle Speed, it will try and maintain the programmed idle speed by moving the ISC/IAC pintle in and out and change the ignition timing.