[Musikmann]

You might still have some error codes stored that were not serious enough to trigger a Check Engine Light or other warning on the cluster. The best place to start is to have them read (AutoZone, PepBoys and places like them will do it for free) amd post them on the forum specific to your car. I believe you have a W203. Good Luck!

 

[Check Codes]

Actually, the BEST place to start is to complete your BW profile by clicking the User CP link and putting your vehicle and location into your profile. After all, if you're not in the US a recommendation to visit Autozone won't do much for you.

But I otherwise agree that a clever point as regards your car is to get the codes read, even with out a CEL you may still have a stored code that can point you to solutions.

If you don't have a code I'd lean towards a Crank Position Sensor based upon your description of the problem.

Take care and enjoy the ride,
Greg