My 93 300E has 3.2 with 220,000 miles. I bought the car used about 10 years ago with 90K miles. Don't know if the wiring harness is bad but I am noticing things like the car will trigger alarm if I unlock and open from driver's door (my workaround is to unlock from the trunk). But this only happens in rainy season.

Also, the ETA has gone bad. Just took it off and saw wires (especially on the 7 smaller gauge wires) all bare. I'm working on manually fixing this with shrink tubing. But I'm afraid shrink tubing may not hold well because it has upper limit of 135 degrees. It can get hotter inside engine.