I seem to remember that the check engine light came on,but this happened about two years ago. Code on computer indicated problem with Mass Air Flow Sensor.
Mass Air Flow sensor failed, replaced unit,car runs fine. Do not waste time cleaning or trying to clean sensor, to delicate & most likely to damage it in attempting to clean as very fine wires as the sensors on a silicon wafer chip. Took it appart to see after installation of new one.
I just had this problem repaired because of the code due to the check engine light. I am still having a problem sometime when I hit the accelerator and the car hesitates before it moves into gear. I have to take the car back to the repairman.
Took it in after the Check Engine Light came on & also because of it's slight delay when exilarating & the engine was sounding a little rough. The mechanic didn't notice anything wrong & fixed the Check Engine Light problem....so I thought. When I started it the following day, after about 15-20 seconds, it came on again.
Well apparently I was driving home from work one day. It was a Wednesday just gotten off the freeway on the wsy yo pick up the kid's. All of the sudden my car started shaking , when I floored it wouldn't pick up. So I pulled over turned the car off anf sat there trying to diagnosed the the problem. Turned the car back on magically went away. Check engine light came on (california) automatic fail. Took to my friend smog shop read out p codes . Misfire from cylinder 1 running to lean. Come to my surprise and investigating 4 yrs ago they tried charging me $5000.00 for a camshaft solenoid leaking, ODB sensor, MAFS When it was their engineering issue. Mind you this was still when I had a loan still with Mercedes. Good thing I still have that paper come tomorrow right after work. Tell you how it goes 3/17/2014