It sounds like speed related problem, check following:

RPM/speed sensor on the back of Compressor.
Check your A/C belt, it might be slipping.
Low freon can cause this situation also, since at low pressure compressor will cut.

Hope this helps

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87 420 SEL
Looking for a nice mid 80's MB diesel.
87 BMW 528e (Sold)
99 TOYOTA 4Runner
1989 Honda Accord (Sold)
1988 Honda Accord (Total)