how do you tell if an idle air control valve is bad? my engine is idleing about 1000 RPM and i was tinkering under the hood the other day when the car was idleing and i unplugged the iac and it didnt change the idle at all, is this an indication the iac is bad?

 

Not necessarily. Remove the iac and see if it and the passageways in the housing need cleaning out. Also, while it's out, very gently push the pintle back in some way to the actuator. Then while you're holding it get someone to turn on the ignition but not start the car. Or if you can place it where you can see it you can do it yourself. It should move but don't let it move more than a small distance before turning the ignition off. If it didn't move it's probably bad. If it moved it may not be bad so try other stuff first. I found it easiest to remove the throttle body and give it all a good clean. Be very gentle with the iac if you clean it and don't get cleaner inside it. Good Luck.

 

iv cleaned the passage way and the intake

 

Can you feel or see it move?