Questions & Answers for: GMC Suburban iac

...to dead if I let off the pedal. It drives fine but will not hold any rpm's in neutral. Check IAC motor, or vacuum leak

1990 v1500 gmc suburban 5.7L, what is the proper Just replaced the IAC VALVE, what is the proper depth of the plunger? i do not know but give these websites a try www.alldatadiy.com and ...

...the TPS (Throttle Position Sensor) It is usually on the opposite side of the Throttle Body as The IAC (Idle Air Control Valve) which I believed you've already replaced. I too have a 92 GMC 350 but ...

...a rough idle due to bad alternator. You have to check outside the box, im willing to bet that your iac motor is bad. When you r iac (idle air control is bad it will idle down and rough under any

...compartment? If not, suspect the idle air control valve. I have pasted test procedures for the iac below. Be careful not to confuse the tps with the iac. The tps is centered on the ybro5ttle

1995 P30 7.4L IDLE HI 1200 RPM SHOULD BE 850 RPM can be the IAC valve, purge valve, and possibly MAF sensor.

...The RPM must be at a set RPM to maintain the charging system at idle.This is acheived by the IAC (Idle Air control). If the battery light comes on and the RPM is within its target range,The ...

...by a false air like EGR,You say hard to start,it can easily start with a EGR open because the IAC will step close,Check vacuum hose ...

...like it is running rich. fuel pump and vacuum hoses sound like reasonable fixes? Idle air control (IAC) control rpm idle during idle. Test it on idle with ALL electrical on full force. RPM should ...

...to be sure the idle air control is working properly and also the engine temp control sw. The iac only comes on to maintain the idle when the engine is cold. The ect sw monitors the outside