Pulsing Idle Disappears when Idle Air Control Valve is Disconnected

[2knob]

Originally Posted by RXtacy

The ISC valve could have gotten dirty, gunk tends to build up in the solenoid. Have you tried removing and cleaning with carb cleaner?

When I removed the ISC, it was very clean, and the one I replaced it with was very clean too. I would think if it was stuck, it would tend to act the same as disconnected (relative to the idle air screw). I'll have to take a closer look at it, and see what makes it tick.