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1991 Mercedes Benz 300se Repair Question


Topics covered: Heater, Coolant, Heater hose.
Mileage: No information provided.

Asked on February 15, 2009

Mercedes Benz 300se Heater Problem

Heater problem
1991 Mercedes Benz 300se 6 cyl Two Wheel Drive Automatic 120,00 miles

My heater is working erratically. It will defrost the windshield. but the cabin temperature does not reach the temperature that I set it at. The blower is fine but all I get is cool air blowing.
Avatar Asked by mrdan89

Answer

Replied on February 15, 2009

Sounds like you may have a faulty heater exchange valve. When these fail coolant is restricted into the heater case producting merely cool air out of you a/c vents. The heater exchange valve is located on the firewall. Follow the heater hoses to the metal exchange block on the firewall.

Tiny Answered by gfimotorcars (expert)
691 answers provided