Temperature Gauge on 1990 100

[Larry C. Leung]

Subject: Temperature Gauge on 1990 100
Ted,

The temp sensor is a common failing, its actually the MultiFunction
Sensor
located on the coolant flange towards the front of the head on the
driver's
side of the car (think upper radiator hose). It's the largish 3 (or 4 if
it's old)
wire sensor, brass, that is under the flange. The usual issue is any
leaks
tend to get trapped in the rubber boot covering the wire terminals,
shorting
something out. Probably worth replacing (about $40 from places like TPC
or Clair Parts on the vendor list), just don't put the boot back on. For
illustrations
of the sensor, it wouldn't hurt to check out Scott Mockry's site, the
ABC's of High
Boost ( sjmautotechnik.com ), which, although intended for the 10V turbo
cars, is
still likely chock full of useful info on the Aspro engine on which the
MC turbos are
based. Welcome to the "lesser" list.

BTW, the instrument cluster is also a source of intermittent readings,
similar issues
to the V8 Instrument cluster. If my oil temp guage reads low and I've
been running,
a swift wack of the dash usually brings it back up (I know, I'm going to
need a
solder job). The fact that Autocheck isn't working says that this MAY
also be an
issue, or it could BE the issue. If you have a Bentley's, I probably has
check values
for the MFS, but I haven't checked in awhile since those sensors do go
kablooey.

LL - NY '89 200Q, Pearl, A4 5-spokes, H+Rs


To: quattro at audifans.com
From: Theodore.Haug at rrd.com
Date: Thu, 14 Aug 2003 12:13:42 -0400





Hello to all!

I have long been a lister on the V8 list, but with my recent acquisition
of
a 1990 Audi 100, I have started receiving the posts from the main list.
I
have bee lurking for awhile now, but have a question I would hope someone
might have the input I need.

The 100's instrument cluster works well, with the exception of the water
temp guage and the auto check/clock set button.  I can live without the
clock and the autocheck feature.  But I was hoping someone might be able
to
point me in the right direction for repairing the temp guage?  Wondering
if
it usually the sensor that fails or the guage itself?  I would guess the
sensor, but I don't even know where to look for it?  Any insight would be
appreciated.

Thanks in advance,

Ted Haug
90 V8 quattro
87 Coupe GT
90 100 automatic