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vacuum leak in MCC 940 900 1993

Hello,

I have a 1993 945T with the manual climate control. There is a vacuum leak somewhere between the manual climate control knobs and the heater control value. The heater control valve itself if okay and will close when a good vacuum is put on it, but the vacuum from the MCC is not sufficient. (When the temperature dial is set to the lowest value, a vacuum signal should close the heater control valve.) I can feel a bit of vacuum at the end of the line that connects to the heater control valve, but it seems weak. There is a hissing sound when the temp dial is set to the lowest value. What are the common things to go wrong? Is it common that the MCC dial would get a vacuum leak in it, or is it more likely that the tubing between the MCC and the heater control valve is the issue?

Thanks,
Steve






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New vacuum leak in MCC 940 [900][1993]
posted by  SLong  on Mon Aug 1 12:40 CST 2011 >


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