1991 Mercedes-Benz 300SEL Repair and Maintenance
A guide to problems, costs, maintenance and repair for your 1991 Mercedes-Benz 300SEL
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1991 Mercedes-Benz 300SEL ProblemsBad Switch/Blower Motor Resistor Assembly May Cause Inoperative Heater Blower Motor
Other than a defective motor, a bad switch or blower motor resistor assembly can cause an inoperative heater blower motor.
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.
The fuel pump and/or fuel pump relay can fail, causing the car to crank over but not start. Proper diagnoses will be necessary to confirm if the pump or relay is at fault.
1991 Mercedes-Benz 300SEL Questionswhere is the fuel pump relay located at on a 1991 300SEL (1 answer)
had been running, but taking awhile to start. Then it is just turning over and will not start at all. Put some starter in breather, no firing, just turning over
Emer.brake switch works
no fuel is present at end of fuel line before injecter.Presure present at distributor