according to your other posts you have a 97 c-class. do a search for duovalve here and you will find some answers. the part is pretty easy to change by yourself. check with phil here on the links at the top of this page for a price (buy parts.)

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1994 C280
2009 VW Tiguan
1993 Toyota X-tra Cab SE-5


1973 220D ... Gone, but not forgotten
1991 Alfa Romeo 164L Gone, wife MADE me forget it

2006 Hyundai Tucson... just straight out FORGOTTEN!