Mercedes-Benz S420 Repair and Maintenance

A guide to problems, costs, maintenance and repair for your Mercedes-Benz S420

Mercedes-Benz S420 Problems

Problems with the pneumatic system can cause closing assist and door lock issues.

One or more door windows may stop working due to a failed window regulator. Replacement of the failed regulator will be necessary to correct this concern.

A faulty mass air flow (MAF) sensor can cause erratic/rough engine operation and fuel economy issues. Since this sensor measures the actual amount of air entering the motor, when it fails, the engine control module (ECM) takes the wrong information and delivers incorrect volumes of fuel to the cylinders.

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Mercedes-Benz S420 Questions

what can go bad after I tried to drive this s420 mercedes with degraded engine wires meaning wires got too old and got broken touching each other car started shaking back firing then stop running we change the harness wires but the car don't want to start need advice plz

car stop running after I tried to drive it in the garage I just change the harness wires and the car still don't want to start n still back firing need advice please thx

car started miss firing and stop running put a new harness but the car don't want to start need advice please thx

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Mercedes-Benz S420 Recalls

THE DRIVE BELT PULLEY ON THE ENGINE CAN DEVELOP FATIGUE CRACKS IN THE METAL AND BREAK. IF THE DRIVE PULLEY BREAKS, THE CAR WOULD NOT HAVE ENGINE COOLING, BATTERY CHARGING, AND/OR POWER STEERING.

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Mercedes-Benz S420 Reviews

what cause my S420 Mercedes to lose power when accelerate from stop it sound like the plug missing fire it does it after driven a few miles stopping to a stop it get worse as I go along and stop at a red light or stop for any purpose.Sometimes when I shut car off and let engine cool down about30 to 45 minutes the car will run better.

I've owned my 1995 s-420 since 1999, and have been relatively satisfied with it. My main concern is that there is a slight vibration that I cannot get rid of. I've balanced the tires, replaced all four tires, had the drive train checked all to no avail. This has been going on for the last 8 years. It looks like it is something that I will have to live with. The heating system is slow warming...

My asr light is,on what is the problem and cost

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