On 10/13/97 I posted a note ("Idle Stabilizer fix?") requesting information
on the sudden racing idle problem.  I received several replies and
suggestions but the most helpful was from Jim Davis who refered to his
earler note to the vanagon list and suggested I might have a defective
voltage stabilizer in my idle stabilizer control module.  That was exactly
the problem.  I replaced the voltage stabilizer ($2.75) and my regulated
idle returned.  I also have a second component in the idle stabilizer that
is somewhat scorched but I couldn't identify it and it didn't look too bad
so I left it alone.  I hope this unknown component is not the reason for
the blown voltage stabilizer.  If it fails again, I will certainly let the
Vanagon list know.  I am including part of Jim's note to me because it
describes the situation precisely.

Thanks Jim,

Ed McLean
'86 Westi
North Carolina

This is part of Jim's note to me:
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It might be your idle stabilizer control module.  A while back I wrote the
following:
========================================================
Recently I related the story of my 87 Syncro suddenly developing a +4,400 RPM
idle.  I traced this to the Idle Control Module located forward of the
right/rear taillight.  The dealer said list was $208.  I called several
wreckers and was quoted from $80 to $20 for this item.  I bought the $20 one
and it arrived yesterday.

Meanwhile I was pursuing repairing the bad module.  Inside the module I
discovered two components that were suspect.  The first one, a voltage
stabilizer transistor was definitely fried.  I found (from my 88 Vanagon
module) a company logo: SGS in tall narrow letters pushed up against
eachother & other numbers were BD 438 and 9  741.  I found that an ECG or NTE
185 was a replacement component for it.  The other component was a rectifier
diode that had some signs of being overheated but was not overtly fried as
the other component had been.  The diode had the numbers  GP15G-7001 and GI
   8641.  I thingk the GI is for General Instruments.  Well, found that it
could be replaced with an NTE 125 or ECG 125.

Yesterday, I installed the two new components and the bottom line is that
after poping the module back in, my van idles normally again!  :)

Cost?
NTE185:   $2.25
NTE125:     $.88

Total:       $3.13 + tax

Compared to dealer list, I saved about $205. - that's 98.5% less!!  :)   :)
  :)
So now I've gone from needing a new module to having a spare for future use.
:)

Jim Davis
87 GL Syncro
88 GL Wolfsburg
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