1990 Mercedes-Benz 300E 4MATIC Repair and Maintenance
A guide to problems, costs, maintenance and repair for your 1990 Mercedes-Benz 300E 4MATIC
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1990 Mercedes-Benz 300E 4MATIC 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.
One or more blend door vacuum actuators may fail resulting in the incorrect output temperature from the HVAC system. Failed actuators will require replacement to restore proper HVAC operation.
A vibration felt through the center floor of the vehicle can be caused by driveshaft flex discs, which crack and shred, causing excessive driveshaft movement. Not repairing these can cause damage to the driveshaft center support bearing, or, in the worst case scenario, damage to the transmission or differential.
1990 Mercedes-Benz 300E 4MATIC QuestionsMuffler wont stay up on car (1 answer)
have taken car back to shop about 10 times they keep putting new clamps on muffler but it will only hold it up for a short time i think its the wrong muffler but they say not