[W126 Coupe] Re: Running Hot update

[Pavel]

Yeah, the more I think about it the more it seems that there is something
wrong with my wiring.  Used the car today to go to work.  In the morning
the temperature was perfect right above 80.  I tried driving really fast
for a mile right before I got off the highway to see if it will heat up
once I start doing city driving temp still stayed perfect.  The car did get
up to 144 mph actual speed since it took me about 25 seconds to drive a
mile. Speedometer indicated between 155 and 157(it was mostly down a hill).
Slowed down to about 140 on the speedometer going up a hill. That still a
lot faster than I thought the car could go being a euro 380 that is almost
stock.


When I got to work I opened the expansion tank cap it was under pressure
some air came out.  After that it ran for the rest of the day at 90 deg
again.  Outside temp was in the 50's deg F today all day.  I have switched
the gauges and they behaved identically. Both gauges do something weird if
I have the car in the car running they show 90 degrees.  If I shut the car
off and put the key in the on position the gauge reads a hair above 80
normal running temp.  As soon as I start the engine it will read 90.  Most
off the time but not always keeping the car at 2000 rpm will bring the temp
gauge from 90 to a hair above 80 within 5 seconds.
Both of the temp gauges that I tried also do something weird while the
engine is shutting down after pulling the key out they peg out at the max
temp for an instant and then go to 0.  If I have the car in the on position
but not running and take the key out the gauge goes from 80 deg right to 0
without pegging out. Also if I take a fast left turn the temp gauge moves
down about  5 deg C.

Does that sound like a bad connection somewhere or both of temp gauges that
I tried are broken exactly the same?  I will get the infrared temp meter to
see what the actual temp of the thermostat housing is before I spend any
more $ on it.