W203 Coupe problem

[Simonish]

I dont know if anyone can throw any light on this for me, I have a C220 Auto Coupe, in the last couple of days after about 15 mins of normal driving, the engine power drops and I cannot accelerate in any gear beyond 3000 rpm, I am taking it to a "stealer" next week (earliest they can see me!) but I wondered if anyone could suggest what it may be, the engine sounds normal it just won't rev above 3k, everything works fine for 15 - 20 mins and there are no computer faults showing up at all - confused, that'll be me then...

I posted this in engine forum too, not being sure of the fault

Simon

 

[fuzzer]

Could be your Mas.

plenty of info on the board if you search for maf or mas.