Hi all - been searching for a while but I don't see any threads that seem to apply. Here goes: 93 400E, 140K miles, trouble of hesitating/nearly stalling has been very intermittent since 100K miles. So infrequent that I could never duplicate it for my local MB shop. Usually runs fine, but out of the blue it will just bog down, shudder, wants to stall. Only happened during warm, humid weather - never during the winter, and only a few times a year. I eventually limp it to my destination, and the next time it's started it runs fine. However, over the past month it suddenly got much more frequent (weather doesn't matter). Giving it more throttle only makes it worse, so I kind of feather the pedal and coax it along.
If I hold it in a lower gear, it usually clears up - and surges when it does - above roughly 3K RPM or so. When exhibiting this behavior, it will "catch", and lunge, then bog down again. Seems like ignition trouble to me. I changed the plugs a while back, but it really didn't seem to help. Last week I changed the O2 sensor, no joy. I see there are a couple sensors available for this model, but I can only think the mass air sensor might be giving bogus or flaky readings. One can't pull codes on the car because it doesn't offer that feature - although there is surely some computer management. I think you can on the 1994+ models.
Anyway, thoughts welcomed as to what I might try next. Maybe mass air or a different sensor? It's only running well maybe half the time right now, so I can't trust it.
10-05-2009, 12:57 AM
Linear Mode
