Idle Air Stabilizer
 

I have an '85 auto and I am in process of refurbishing the intake system. I checked my idle air stabilizer and mechanically it seemed free, but electrically it did not energize in either direction. I took it apart, PATA to get those tabs revised to allow the can to open, and all looked OK inside electrically. I also confirmed that the mechanical parts were all free to rotate. Holding the pieces together and checked electrical function again and it seemed to function correctly in both directions. So I restaked the can in place and now it doesn't work again, :grr: . This thing doesn't look all that complicated but I can't figure out why it will work sometimes and not others.

Any suggestions would be appreciated. I guess I could just replace it, but there are a lot other places I could use the money if I can just figure out how to find a reliable fix. :bowdown:

This is just a guess, but perhaps the bearings are worn and in some orientations, it will work, or it will work until the bearings get jammed just a bit and then...

I believe this is basically like the 87, it rotates on an axis or shaft and while I haven't had it apart, it must have some sort of bearing mechanism for the shaft to rotate on/in. Can you check the rotating mechanism for lateral movement? (assuming it's like the 87

Intermittent failure is the worst of all possible worlds. Good luck.

Rod

What was the method you used to determine that the idle speed regulator did not energize in either direction?

I'll quote to you from the Porsche 1985 tech update (my inputs in blue). From the LH control unit the air regulation valve recieves a cycled voltage signal (100 Hz) which acts on both windings alternatively during a positioning period. This produces an opposing rotating forces on the armature. Due to the inertance of the armature, the valve is set to a certain angle, which is equal to the duty cycle of the applied voltage.

I was appling battery voltage to the exterior terminals of the three terminal set, with the center terminal grounded (off the vehicle). The ground was connected and I would touch the positive to either of the terminals alternately at no particular frequency. I will take it apart again to see I fried any of the internal electrical as I did not limit the current supplied.

Thanks for the information.