Date registered: Sep 2006
Vehicle: 2004 CLK 240 Coupe
Location: Norfolk. UK
Mentioned: 9 Post(s)
Quoted: 343 Post(s)
Welcome - but you might have done better to have posted in the forum specific to your own model. That is the W124 forum, which will have many owners of similar cars and who know the symptoms of typical faults. 'General' is for topics about ALL models.
Well done for a good description of your problem, and I'm going to admit that I know little about MBs of your era. Somebody else will surely be able to give some relevant advice.
However, as a long-time car owner, and DIY fixer, I will take a punt and suggest that ignition problems generally occur across all engine rev ranges, not just the bottom end. On the other hand the MAF is affected by engine air intake, so it could be your problem. They do need changing from time to time. Some folks have managed to clean the sensor, but generally they are replaced. If this is done, take note of this entry I found in the WIS for your model.
"misfiring, bucking, or surging due to defective engine wiring harness in the area of the MAF" . "Usually no DTC stored"
So there is a known issue here, and if your MAF is changed, the associated wiring should be closely inspected.