Date:         Sat, 11 Jan 2003 16:32:17 -0500
Reply-To:     Marc Perdue <marcperdue@ADELPHIA.NET>
Sender:       Vanagon Mailing List <vanagon@gerry.vanagon.com>
From:         Marc Perdue <marcperdue@ADELPHIA.NET>
Subject:      Idle Problems, update, kinda long
Content-Type: text/plain; charset=us-ascii

Okay, Mark solved the mystery of the loose wire . . . it goes to the A/C
which I don't have.

I pulled the idle stabilizer control unit and opened it up.  It smells
like it's toasted, a kind of burnt electronics smell.  The voltage
regulator looks okay, as if I could tell what it would look like if it
weren't okay.  :^)  The big gray component on the upper right of the
bottom board looks like it's burnt.  There was some discussion of the
power transistor being a likely culprit, but it doesn't appear damaged
in mine.  Robert Fish pointed out that a bad idle stabilizer valve could
burn out the control unit, but there doesn't seem to be a sure-fire way
to test the valve other than to see if it's buzzing.  Grrr!

Joel Walker, in his infinitely helpful capacity, gave me scads of info
about diagnosing idle control module problems but they are way more
complicated than I feel comfortable handling at this point.  Thanks just
the same Joel!  The exec. summary of all that info is that the following
are implicated in idle/performance problems: throttle switch, idle
stabilization controls, Temp II sensor, and the evaporative emissions
system.  Poor performance at operating temp. and at full throttle can
also involve the fuel system and the ignition system.  This seems to be
less likely the case in my situation.  The idle stab. control unit also
receives input from the auto. tran. selector switch.  Is this in the
tranny itself?  If so, I'm working with a decent, fairly recently
rebuilt AT from Long Enterprises, so I don't think that's at issue.
Also a player in all this is the power steering pressure switch.  I've
noticed no problems with my power steering, nor any change in idle when
steering, so I'm temporarily ruling this out as a culprit.

This much is clear:
1) My breather hose is bad (evaporative emissions system)--I'm going to
replace it.  Volkscafe is the only place, on-line, that I've been able
to find this and their price is $8.75.
2) My idle stabilizer valve passes the one test that VW says you can do
on it; it buzzes.  I'm going to assume for the moment that it's okay.
3) My idle stabilizer control unit looks and smells toasted.  I'm going
to replace it.  Incidentally, the best price that I've been able to find
this for so far is $184.75 from Volkscafe.
4) The Temp II sensor is fairly cheap.  I'll buy one and replace it if
the other parts don't take care of the problem.  If they do, I'll have a
spare.

I will replace these parts one at a time to see where the culprit is and
to see what problems get fixed by what and give you all an update at
that time.

Thanks all for your forebearance during this time when I'm filling up
bandwidth.
Marc Perdue