Looking at some things on my daughters 83 240D.

At idle the vacuum hose going to the compressor is pulsing. The AC runs fine but I have never seen the pulsing effect that the car is doing.
Anyone heard of this?

I have not put gauges on the car, I will do that this weekend. I will also check the evaporator temperature sensor this weekend. It may be allowing the evaporator to freeze up and the expansion valve is freezing up which makes the line pulse. Its sucking as hard as it can but no freon gets through.

Any ideas?

Dave

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1970 220D, owned 1980-1990
1980 240D, owned 1990-1992
1982 300TD, owned 1992-1993
1986 300SDL, owned 1993-2004
1999 E300, owned 1999-2003
1982 300TD, 213,880mi, owned since Nov 18, 1991- Aug 4, 2010 SOLD
1988 560SL, 100,000mi, owned since 1995
1965 Mustang Fastback Mileage Unknown(My sons)
1983 240D, 176,000mi (My daughers) owned since 2004
2007 Honda Accord EX-L I4 auto, the new daily driver
1985 300D 264,000mi Son's new daily driver.(sold)
2008 Hyundai Tiberon. Daughters new car