1987 420 SEL.
Climate control is set which requires a mixture of cool and hot air. Temperature should remain constant.
As the climate control regulates itself heat is sent into the cabin for an extended period. Sometimes a "clap" is heard as if a door is suddenly closed, prior to the heat abating. Sometimes after the car is turned off and then restarted while hot, hot air comes into the cabin for awhile before the temperature finally reaches the set level.
Any suggestions?

[This message has been edited by hewv7 (edited 05-11-99).]

More info is needed here. When Where and How does it happen??? Explain in DETAIL.

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Benzmac:
ASE CERTIFIED MASTER AUTO TECHNICIAN
LEAD TECHNICIAN FOR 14 BAY FACILITY
MERCEDES SPECIALIST 8 YRS
PARTNER IN MERCEDESSHOP.COM

I edited the first message. However the heat problem occurs whenever the climate control system is on. It appears that a shutoff for the hot air is sticking in the open position therefore more hot air is fed into the cabin than the thermostat is calling for.

Maybe a faulty monovalve?

Replace the monovalve insert. Pay attention to the washers and the large spacer that goes inside.

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Benzmac:
ASE CERTIFIED MASTER AUTO TECHNICIAN
LEAD TECHNICIAN FOR 14 BAY FACILITY
MERCEDES SPECIALIST 8 YRS
PARTNER IN MERCEDESSHOP.COM

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