Hi I'm new here and hoping to get some advice.
Car: Merc. C 220 elegance 1994 petrol Auto UK model
Problem : Limp Home Mode
Turn ignition key = engine starts = idle climbs up to 1000 RPM then goes
into L.H.M. = switch of ignition = restart and the same thing happens.
the car used to travel approx. 15 miles before it went into L.H.M but by quickly turning the ignition
On/Off while driving you would get another 2 miles or so, I then lost interest and put the car on hold for a year
and bought a 1995 E200 petrol estate this had to have a head gasket replaced and now has a problem which is:
when cold and first started it drives fine but after a few minutes of running the idle becomes lumpy intermittidley
and feels like its firing on 3 until it picks up speed then its ok , meaning it drives fine on motorways etc until you stop at a junction and need to drive off again also I'm sure I can sometimes hear faint backfires when driving off from a standstill.
could it be the coils for the spark plugs breaking down and causing the excess fuel to explode.the fuel consumtion appears to have increaced.
thanks

Brian

I always thought the limp home mode was unique to ASR cars - and wouldn't think a 94 C220 would have ASR, or perhaps it does, but you don't mention the ASR warning light. In any case a limping car is not always in the limp home mode - it's sometimes just a limping car. Not sure what diagnostic system you have but would think reading the codes would be the next step.

have u checked the injectors?
bad injectors can make an engine temporarily in rich condition do to poor atomization, but once theres enough airflow going in to the cylinders the unatomised chunk of gas would be burned. i takes a few cycles to burn all of the unatomised fuel inside the cylinder that is probably why your car hesitates after a few minutes stop on the traffic light. how does the car starts when it's cold?