sounds to me as though the blower motor regulator is faulty.from your description you could also have worn out bearings in the blower motor.what! you say it's only 15 yrs old [should still be under warranty ha.ha.]

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David S Poole
European Performance
Dallas, TX
4696880422

"Fortune favors the prepared mind"
1987 Mercedes Benz 420SEL
1988 Mercedes Benz 300TE (With new evaporator)
2000 Mercedes Benz C280
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