winecountry400E

Hello folks; it looks like I'm a newbie but I'm back for the second time after being away for a few years..

I have a '92 400E which has been a great car for me. Just recently it threatens to stall or rough idle and runs 'choppy' at low speed (under 35mph. Above that, it's smooth sailing. What could this be? Bad 02 senser, fuel filter (it was replaced at 106k-I now have 165K)? From what I have seen on inspection, the wiring harness looks great and no fraying.

Thoughts? Great to be back. Cheers!

winecountry400E

UPDATE: I got the 400E up to highway speeds today and the choppiness, intermittent surging/lagging continues. I am taking it to my MB tech on Monday and will have him look at fuel filter, plugs, plug wires, fuel pump, fuel relays and such. The wiring harness looks great and am assuming the first owner got the MB Service Bulletin and had it changed out.

I'll check back in next week and let you know what found.

John M.

Your 92 was not affected by the wiring harness issues. Only 93-95 had the biodegradable harness insulation.

winecountry400E

Thanks John. I did some research later and found that was the case; the stuttering became worse to the point yesterday that when I started the car it would for a second then die. This whole issue was increased over the last several days. It was towed to my MB tech yesterday. I'll find out Monday. Maybe plugs, wires, something to do with the fuel delivery. We'll see..

winecountry400E

....soooooo, here we are a couple of weeks later; the car got to the point where the starting and drivability got to the point we had to have it towed to my MB tech. Turns out the wiring harness WAS the culprit, as well as distributor caps and rotors. 1,600.00 later, she runs like a champ.

Jim's500E

All W124 M119s V8s had the bad wiring from the factory ...including the 1992s.

190E 16V

Wish I'd seen this earlier. My '92 had a bad wiring harness at 60K miles, this year.It looked fine, but still, it was cooked!
You need to cut through the insulation a bit with a penknife, to check for corrosion.
Oddly, a similar 90's SL in the shop, had a harness that looked terrible, but no symptoms.

Mine lasted 18 years and I knew it would fail inevitably, so I'm not bothered by it.

Something every MB owner of a car of that vintage should be aware of.

Glad it's taken care of.

winecountry400E

The differnce in the harness, ditributor caps and rotors and recent plugs/wires has it humming along just fine. I called my MB tech this morning to get an idea of what a timing chain/guide replacement would be just as a 'prevent' and he said about $1,200 for the chain and the labor would put it over $3k as the book says it's about a ten hour job. He also recommended since they were going to virtually the front half of the engine off, replace the water pump as well. I have meticulous records since 60k but nothing before that. 165k and we'll definitely keep for a while. Plus,the interior is virtually flawless.