Idle Stabilization Valve Question

[kylemason]

Should the valve really vibrate with the ignition key on? I feel no movement in mine with key on, engine running or not.
1988 2.1 Automatic.
I am still having a small idle 'hunting" issue and am running the tests. The valve does snap "smartly" open and shut when 12 volts are applied as per 10cents post in the search.
Thanks,
Kyle

[MrPolak]

Mine hums and vibrates with ignition on.

[kylemason]

That's what Bently says, I just never knew if it was really noticable or not. I guess I'll be checking the wiring tomorrow.
Thanks, Kyle

[MrPolak]

I can hear mine buzzing from time to time while sitting at a stop light.

[Terry Kay]

If it isn't vibrating with the ignition on--it ain't right.

You should hear it buzzing, or at least feel it with your hand on it.
_________________
T.K.

[crazyvwvanman]

The buzzing with just key on depends on the FI wiring harness version you have. Your 88 should only buzz for a second when the key is turned on and then continuosly only while the engine is running. Older 2.1 buzzed all the time the key was on but starting in 88 the idle unit gets its power from the fuel pump relay and so only buzzes when the fuel pump is running. (before that it got its power from the ECU relay, on with the key)

It is pretty common for the idle control unit (idle relay, ICU, etc) to fail and the part inside it that often fails is the driver transistor that makes that valve buzz. If you grab the valve while the engine is running you should feel it vibrating though you probably won't hear it. If you don't feel it I would try to borrow or buy a used ICU relay. It lives behind the pass side tail light assembly. Remove the light and look way in there.

Mark