1990 Mercedes-Benz 420SEL Repair and Maintenance

A guide to problems, costs, maintenance and repair for your 1990 Mercedes-Benz 420SEL

1990 Mercedes-Benz 420SEL Problems

Bad 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.

Stuck Idle Air Compensator May Cause Too High/Too Low RPM

It is not uncommon for the idle air compensator to get stuck in one position, resulting in the engine idle speed (rpm) being too high or too low. Replacement of the failed compensator may be necessary to correct this concern.

Replace timing chains/guides every 100,000 miles
The timing chain and timing chain guides wear; they should be replaced every 100,000 miles.

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1990 Mercedes-Benz 420SEL Reviews

what other automobile would you even consider that has 150k miles and still cost $5k or better..and get a consistent thumbs up!

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