Resources for the Repair and Maintenance of your Mercedes-Benz S420
Mercedes-Benz S420 Models:
Mercedes-Benz S420 Problems
Closing Assist/Door Lock Issues Due to Pneumatic System Problems
Problems with the pneumatic system can cause closing assist and door lock issues.
Power Window May Fail Due to Window Regulator
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.
Erratic Engine Operation and Poor Fuel Economy Due to Faulty Mass Air Flow Sensor
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.
Electrical Issues Due to Degraded Engine Wiring Harness
The engine wiring can degrade because the insulating material falls off leaving the bare wire exposed. This can cause many problems depending on which wires are exposed and what they touch.
High Usage Vehicles May Experience Ignition Lock and Tumbler Failures
Due to wear, high usage vehicles can experience ignition lock and tumbler failures. The ignition lock cylinder will generally require replacement to correct this concern.
Mercedes-Benz S420 Recalls (Recent)
Mercedes-Benz S420 Recall 96V058000
Summary: 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.
Learn more »Mercedes-Benz S420 Questions and Answers
Have replaced the theromstat and water hoses.
it smoke when in park or stop at a light
THE ABS LIGHT SAYS ON. AND THE ODOMETER STOPPED WORKING. PLEASE HELP. THANK YOU!
the odometer stop working. what cause it to stop? how do you fix it. the odometer just stop and resetting the trip meterdidnt help. need quick answer.
I am trying to locate the expansion valve on my 1994 s420. CAN ANYONE HELP ASAP.
Mercedes-Benz S420 Reviews
heater dont work and shifter dont work it go in different spot drive is revers 3 is drive. what can i do.
My asr light is,on what is the problem and cost
I like this car, it is a 1994 S420, I had it for 6 years the main problem was the transmition, I have to build it twice. It has some electrical and minor michanical problems like any other cars the window motor has to be replaced twice, the heater/AC fan stopped workig for no reason, the sun roof gets stuck sometimes, the seats had some movement problem. Driving is enjoyable, engine is super power and very comfortable
OVERALL, THIS IS ONE OF THE BEST HANDLING CARS THAT I'VE EVER OWNED. I'VE OWNED A Z-28 CAMARO, A VOLVO, A LEXUS AND ABOUT 7 TOYOTA SUVs. THE BRAKING IS INCREDIBLE AND THE DRIVE IS LIKE BUTTER. WHAT DRIVES ME NUTS IS THE GASOLINE SMELL IN THE COMPARTMENT PRESUMABLY FROM THE NEW CATALYTIC CONVERTERS WE JUST INSTALLED (FOR THE 2ND TIME). THE STEERING WHEEL PUMP HAS HAD TO BE REPLACED (ALSO FOR THE 2ND TIME). THE HEATER MOTOR HAS BEEN REPLACED BUT THE CAR STILL DOES NOT BLOW HOT AIR JUST LUKE WARM AIR.
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 the car up. However, after twenty to thirty minutes it becomes comfortable. The engine seems to be okay, but I have only 91,000 miles on it. I have experienced problems with the oil lines leading to the lifters in the heads, the lifters would give a slight tapping sound and I would immediately take it to Herb Gordens Mercedes shop department. Each time it cost approximately $1,200 to repair. My car is garage kept and pampered. It goes without saying, I like it very much. However, if I were to purchase another car in the future, I think it would be a Lexus LS-460. From what I've read, that seems to be the most reliable car on the road today.