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*very* Cheap Iac Valve Tester

bill190

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bill190 Enthusiast

bill190

Posted
Posted

As you may know, testing an IAC valve (Idle Air Control Valve) pretty much requires expensive test equipment because it is an electric "stepper motor" and gets "pulses" of electricity to make it operate.

 

Well I have found a way to determine if it is basically "working" as opposed to not working at all. A basic test.

 

You can hear it operate! But only after shutting off the engine. At this time, the IAC valve moves fully forward, then retracts half way.

 

You can hear this with my new handy dandy "IAC Valve Tester". Just take a paper cup, punch a small hole in the bottom, thread a string through the hole, tie a knot on the end of the string, then attach the other end of the string to the IAC valve or the IAC valve electrical connector. Place the cup to your ear and pull the line taught lightly. Then have someone else start the vehicle, then turn it off. And you hear the IAC valve operate through the vibrations on the string and this is amplified by the paper cup.

 

Pictures...

 

Hold cup to ear....

iac_valve_tester1sm.jpg

 

String just wrapped around IAC electrical connector and not touching anything else...

iac_valve_tester2sm.jpg

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