IACV inspection/ operation/ valve movement

[devo]

Following the FSM inspecting the IACV
How much movement should there be with the valve. The dotted lines in the illustration suggest that the valve should move a centimeter or more?
Or fully retracted to fully extended.

 

[petegangies]

from what I have been told it moves in extremely small increments!

 

[CharlieS]

Barely visible movement on each pulse, I used a digital caliper to measure change. A dial guage in a fixture might be better, Mine was buried or I would have used that. As more knowledgable people have posted it is a multi position stepper motor and each step is only a partial (1/4 turn maybe?) rotation. The part that moves is riding up and down a screw inside the housing, the travel distance per pulse is miniscule.

 

[devo]

Since the start of this thread I have put 3 AICV through its paces. I never measured the distance the plunger traveled and I have forgotten how many pulses it takes for the plunger to have gone from full extension to full retraction. I do know that 2 used AICV and 1 new all acted the same on the bench. I know the new one acted differently when installed and the ECU took over operations. The idle speed dropped to near 625 rpm!