Wire Harness/ignition Wires

[92300SE]

Last couple of days I have been reading a lot of posts regarding
possible issues with the M104 engine(that I have in my 92 w140),
I noticed everybody mentioned wire harness issues on 93-95
models,what about my 92(build in fall of 91).Why I am concerned?
Yesturday I started my car briefly in the morning,just to move it
on the other side of the driveway...30 sec.,was cold outside,
32F,everything was fine,when I restarted 6 hours later
it started kind of jerky in 5 cyl.,almost quitting,after I pressed the gas slowly a couple of seconds it start running smoothly again...,maybe a little flooded
from short start in the morning?,or old spark plug wires?,I just
bought the car 1000 miles ago,it ran flawless so far...,only did
highway driving so far.

[jointheir]

I have a 93 300e and i came across the same problem your having now. I have to replace my injector cable harness.. Mercedes said its a coming problem with those years. I would replace the ignition wires and the plugs before you think about buying a harness. If the problem consist, most likely its your injector cable harness.

[Kestas]

Just peel back some of the protective loom and inspect the individual wires of the engine wiring harness. If the insulation looks 200 years old (brittle and flaking), then you have the dreaded wiring harness problem and need to replace it before any further diagnostics.