[tech] Help diagnosing an 8V?

[m-carlson@comcast.net (Michael Carlson)]

> You have a vavle that will increase idle when the A/C is turned on, but it
> is a different beast from the CIS-E ISV.

Ah, yes, the idle speed boost valve, according to Mr. Bentley.  Thanks for
setting me straight.  (Interestingly enough, I can hear the valve click when
the engine stumbles...)

> > > Michael, when you hear the car run rough, does the buzzing of the
> > > frequency valve change?  Sounds like the system is adjusting the
mixture,
> >
> > Dunno, that's a good question.  I'll give it a listen after work
tonight.
>
> That will tell us for sure if the Jetronic brain is trying to adjust the
> mixture.

The frequency valve does not sound like it's changing at all.

> > > bad.  Try hitting the full throttle switch while it is idling, let us
know
> > > how the engine acts when you do that.

When it's idling in a "healthy" fashion, hitting the full throttle switch
makes the idle speed go up a bit, but no other affect.  When it's idling
poorly, hitting the full throttle switch seems to have no effect.  It might
run *slightly* less rough, but it's still unappy.  If I hold the switch down
while it's healthy, it eventually does stumble as it would without the
switch.

I also noted that it's become more difficult to start, now.

Does any of this help?

Thanks again,
Mike Carlson
'84 Scirocco Wolfsburg Edition (slightly ill)
'95 GTI VR6
http://www.divergent.org/mikes.vws/