Hi...

My car, W124 93 320 E, 280k km, starts to shake violently once the temp reaches 85C or more. Putting the Gear in neutral has a very minimal effect on the vibrations. While vibrating, the cars acceleration drops drastically, taking almost 14 seconds to reach 80kph, but i can reach higher speeds though. If I switch off the car then on Again the problem goes but comes quickly as the car is still hot.

I took it to several repair shops and the almost unanimous decision was to replace the wiring harness. After Paying 700$ for the harness the problem still persists. Is there any proper testing procedure to try to pin down the problem, or simply replace all suspected parts (anyway the car done almost 300k)?

One of the repair shops told me before replacing the harness that the ECU (computer) might have been damaged due to bad cabling. Can this be a reason?

I really like this car a lot. I hope to find a solution here.

Thanks

Robin