An unusual fault

I have a 2001 E class 240 Estate which works perfectly most of the time. Occasionally the yellow engine management light comes on and the car tick over becomes rough and may lack power. The car never stalls
and if I stop, switch off, and restart, the problem goes away although the warning light stays on for perhaps three further starts. There seems no pattern to when the problem occurs - sometimes when overtaking at highish revs, other times at low speeds.
The diagnostic system shows there was a fault but not what caused it! I am about to let the Mercedes dealer investigate but would like to give him some advice before I get a hefty bill for his investigation.
Can anyone help?
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Sell it now. It is cheaper to just replace the car. That light can not be fixed. It is ole Jerkin Shrimp's retirement plan.
mcbrue truthfully under the bridge in the trailer down by the river
96 S420
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Thanks for the warning but I could do with a bit more information before I sell it! Can you explain in a bit more detail what you know about this fault?
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John, he is a joker... McBrue owns a W140 that keeps draining his pocket due to all that gremlins... Yet, he still pays for the repair.
As for your situation, if you got a code, then you have to furthur diagnose your problem... there is no such self diagnostic that tells the mechanic what to replace. You still have to investigate by testing associated sensors, check the freeze data information when the error occurred, etc.
If you are technical, then I suggest you try to solve the problem... if you can't then send it to the shop where they have more sophisticated software to help them diagnose the problem.
In majority of cases, most car has common problem so the fix is easy when you recognize it. However, your car is not available in USA, we wouldn't know what that problem may be. I suggest you search internet in Europe area where someone might present you a solution to your problem.
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And no matter what the diagnosis is, a new problem will pop up. These are generaly small cheap fixes, say 150 to $300 US each, but 1 a month adds up.
mcbrue nearbankruptly under the bridge in the trailer down by the river
96 S420 (the best MB has to offer)
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