1994 Mercedes Benz 129 problems

Filed May 23, 2012 · Electrical · 39,000 miles · NH

The wiring harness, of which there are three, was constructed of an insulation case that is by design biodegradable. This was a material selection defect and is causing great expense and pain to owners of these cars. It is also drastically affecting resale value of the cars. Unusual for a car that cost over $100k new. Therefore, the outer case of the three harnesses disintegrates over time, and exposes the individual wires to excessive heat from the 12 cyliner motor - this causes the insulation around those inner wires to crack and disintegrate, and over time leads to failures and hazards - and during model year 94, 95, 96 - and cases are now being reported for model year 1997 - in the sl600 model - it is the r129 chassis and is known to affect other chassis that use the same 12 cylinder motor. The failure rate is nearly 100%. It is not a question of if it happens, it is a question of when it happens. I have contacted mercedes about this, and off the record, they are well aware of the problem - it is a widely known issue on these vehicles, but there is no mandate to correct it or so that is what I was told. . There are many cases listed here with this agency where engine fires or loss of driver control occurs as well - please see other cases listed here. This is a true safety problem. This has not happened to me yet, but I have encountered the performance problems and electrical component failures. It is a very costly repair - both for parts and for labor, and can run upwards up to 8000 to repair. The symptoms of this problem are poor or inconsistent performance from the engine, poor throttle response, or complete failure of the throttle body and mass air flow sensors. Including rough idle, hestitant acceleration, engine fires, engine shut off during operation, failed electrical components.