Some stupid valve
that diverts the coolant to the heater core I guess. I beieve they range in price from around $40 for the old 300's series all the way up to $800 for the s-class like I have. I guess the best advice is dont even think of buying a used 92 or 93 s-class unless you are rich. I thought I was getting a deal , $14,000 for a 93 400SEL with only 139,000 miles. Then I found out what it would cost to fix the stereo, oil tem light, abs light and or brakes.
Im starting to think Mercedes are really over priced pieces of junk.
The Bodies and chassis and engines seem ok, but everything else is expensive and hard to work on.
My 1982 300SD seems like a lot nicer car. Wish it rode like the 93.