Mercedes-Benz 420SEL Repair and Maintenance
A guide to problems, costs, maintenance and repair for your Mercedes-Benz 420SEL
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Mercedes-Benz 420SEL ProblemsRough Running Engine Due to Misfire
A rough running motor or lack of power can be caused by a failed distributor cap or rotor, ignition wires (or their resistors), or valve cover gasket leaks. If the valve cover gasket leaks, oil can pool where the ignition wire resistor connects to the spark plug. The resistor can fail and the spark plug may not fire because of a short circuit through the oil.
Other than a defective motor, a bad switch or blower motor resistor assembly can cause an inoperative heater blower motor.
A refrigerant leak may develop from one or more of the AC hoses. Proper leak detection procedures should be followed if refrigerant loss in encountered. Replacement of any leaking hoses will we required to restore proper AC operation.
Mercedes-Benz 420SEL QuestionsI have no heat or a/c blower works, and I have replaced several parts already (2 answers)
I have replaced the climate control switches, a/c compressor, mono valve, thermostat, I need help and or cost for repairs
The economy needle has gone from black all the way to red.