The relay which turns the airmatic suspension pump on may fail causing the pump to run continuously. This can result in failure of the pump motor or a dead battery as the pump motor will continue to run after the car is turned off. Also, Worn airmatic pump mount bushings can causes noises in the front axle while driving on bumpy roads or a buzzing noise while the pump is running.
2004 Mercedes-Benz S430 4MATIC Problem Reports
Most Reported 2004 Mercedes-Benz S430 4MATIC Problem Reports
High mileage or older vehicles commonly develop leaks from the differential seals and/or cover. Our technicians recommend a complete reseal of the differential unit whenever these leaks are repaired.
Front thrust arm and control arm bushings can crack and sometimes tear completely. If this is not repaired quickly, damage to the front subframe unit will occur, which is very expensive to repair. Updated control arms (that prevent damage to the subframe when the bushings wear out) are available.
The engine may develop a stalling and/or no start condition due to a failed crankshaft position sensor.
An engine oil leak may develop from the oil level sensor. Replacement of the leaking sensor will commonly correct this concern.
An engine Oil leak may develop from the PCV vent housing on the valve cover and/or the inspection plate on the front of the engine.
It is not uncommon to encounter premature failure of the anti-lock brake system (ABS) modulator assembly due to dirty brake fluid. Our technicians recommend flushing the brake fluid every two years in order to help prevent this problem.
The center console armrest can break. Replacement is commonly the recommended repair.
The active body control system can leak fluid from numerous areas, including the tandem pump, hydraulic lines, struts, and/or seals. If it is not repaired, the vehicle ride height could drop too low and cause damage to the undercarriage.
The evaporator temperature sensor can fail, causing the AC compressor not to cycle. If the AC compressor does not turn on, the AC system will not blow cold air. If the compressor is stuck on, the air will be very cold at first, before warming up.
The rubber bond in the harmonic balancer can decay, which causes the balancer to move and work its way toward the timing cover. If the balancer comes into contact with the timing cover while the engine is running, it will fracture and damage the cover and potentially other surrounding parts. The harmonic balancer should be inspected at every service.
The door for the vanity mirror (or the frame for the door) can break; due to a redesign, the mirror "cassette" will need replacement.
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.