No Power to IAC

[redalfa164]

Some reason I am not getting power to IAC valve(NO POWER IN THE PLUG ITSELF headbang this causes code of 81.This is 1991 so it may not have an air diverter solenoid. The results high idle speed (2000-3000rpm).

 

[revhardSHO]

time to dust off your multimeter

 

[redalfa164]

Any experience with this particular code (81)

 

[rangerj]

redalfa164

The circuit is 361. It is a 14 gauge red wire. Check continuity from the 60 pin connector at the firewall to the IAC solenoid conection. See the 1991 electrical diagrams for the pin location in the 60 pin connector.

I think there are a couple of connections between the firewall and the solenoid, any one of which could cause a problem. Track down the power supply for the solenoid and test that.
rangerj

 

[projectSHO89]

Red wire at IAC plug should have VPWR on it. It is the same power circuit as is used by the injectors and other devices. Verify it first.

With the IAC plugged in, backprobe the other wire (Orange/Black). It should also have 12 V (KOEO).

If it has 0 V on it, either the IAC coil is open (it should measure 7-13 ohms) or the Orange/Black circuit is either shorted to ground or the PCM is holding it down.

I would suspect one of the latter two.

Steve

 

[redalfa164]

Thanks guys now I have sense of direction in trying to trace this short.