Donald Snook wrote:
I took a trip 300 mile trip the other day in my 1990 300SEL (128K) and I
noticed that when I was climbing a long steep hill (steep for Kansas,
not steep for anywhere else) my a/c would stop blowing very hard. It
was a very hot day and when the a/c would stop blowing it was
noticeable. When I crested the hills and proceeded down the hill the
a/c would return full blast. This was all at 75-85 mph. Could this be
a vacuum problem? Or something else? The a/c works great otherwise -
very cold. The only time I have noticed this phenomenon was climbing
the hills. It worked great on flat runs. Any thoughts?
If you are talking about how cold the air is, here are several
possibilities:
There is a pressure cutoff that will cut off the compressor when the
high pressure exceeds some limit. This could easily happen in a system
that's been converted to R-134a. There is another sensor that will cut
off the AC compressor when the coolant temperature approaches the safe
temperature limit. Either of these COULD be exceeded when climbing a
hill. There MAY also be a pedal switch that cuts off the compressor when
the accelerator pedal approaches the floor. This was often installed in
cars with smaller engines (relative to the weight of the car).
If you mean that the blower speed changes or the air comes from
different vents, then I have NO idea.
Marshall
--
Marshall Booth (who doesn't respond to unsigned questions)
"der Dieseling Doktor" [EMAIL PROTECTED]
'87 300TD 182Kmi, '85 190D 2.0 161Kmi, '87 190D 2.5 turbo 237kmi, '84
190D 2.2 229Kmi (retired)
