New electronic throttle actuator defective?
 

I have a 1995 E320. The ASR light was coming and and the car would go into limp home mode. A local Mercedes "specialist" replaced the ETA, but the problem persisted. He then replaced the engine wiring harness. Problem NOT solved! I have researched ASR on this website, and see there can be many causes. Is it common for a NEW ETA to be defective?

I stopped payment on a check for $1100 for the wiring harness, but already paid $1800 cash for the ETA and an O2 sensor. The shop wants me to bring the car back, but I hesitate as they dont yet know about the stop pay.

I want to try the brake light switch and cleaning the front wheel sensors. I had the car detailed just before this problem started. Perhaps they power washed the wheels?

It is possible the new EA is defective but not likely. I also think it is unlikely that a defective stop lamp switch would cause your engine to revert to limp-home mode.

I don't want to scare you but it's more likely that a bad EA and/or wiring harness may have damaged your HFM-SFI control unit or some other component.

Did this "specialist" ever pull trouble codes from the car? That is a good place to start. Autozone can pull 'em for you and I think O'Reillys as well. Get the codes and report back what you find.

Good Luck

No, but bad ETA is a common defective diagnosis.