I, too, have wondered about the internal goings-on of this module. Seems
it must have a "clock" to "know" whether the engine is running too fast
or too slow. Otherwise, how would it know?

--
Jack "Rocket j Squirrel" Elliott
1984 Westfalia, auto trans,
Bend, Ore.

On 09/16/2012 01:46 PM, Larry Alofs wrote:
> I'm hoping that someone can give me some details about the 1.9 idle
> stabilizer.  I have been trying to tune-up and evaluate the engine in
> an '84 that I bought for parts.
>
> Does an idle stabilizer contain some type of tachometer?  I understand
> that it adjusts the idle speed by adjusting the ignition timing
> slightly.  Does it watch the time interval between between ignition
> pulses and use some absolute standard to decide if the idle is too
> fast or too slow?
>
> Is the timing adjustment always by the same amount, faster or slower,
> or does it vary depending on how much the idle is out of adjustment?
>
> When setting the timing on this engine, I have just guessed at the
> idle speed, since I don't have any tach.  Afterwards when I reconnect
> the idle stabilizer, I can see the timing jumping back and forth.  It
> seems to jump between just two positions.  It also seems to spend more
> time in one position than the other, depending on how I adjust the
> idle speed using the big screw in the throttle body.  It feels to me
> that the stabilizer would like me to set the idle speed so that it
> spends about the same amount of time in each spot.
> Thus it would be able to do more advance or more retard as needed.
>
> Does this make sense or am I all wet?   David are you there?
>
> Larry A.