Recirculated air flap problem (C208)

[P.Peter]

Hello all,

I have a problem on my CLK 200 Kompressor (Year: 2001, engine code: 111.956) with recirculated air flap, which is on the top of the supercharger. The air flap sometimes does not work. When the engine is cold and i'm starting the car there are two possibilities: the first is that the secondary air injection system doesn't works at all, the second is that the secondary air injection system starts working, the recirculated air flap closes, the change over valve opens the shut-off valve normally, and the air passes through the check valve and the pipe into the exhaust, but after 2 or 3 seconds the recirculated air flap opens fully (90 degrees vertically) and remains open, so there is no boost. In this case i have to manually relearn the recirculated air flap. After that it works normally for 2 or 3 times but later remains open again.
I think that the change over valve and the shut-off valve are in good condition. There are no vacuum leaks. I can also blow air through the check valve and the pipe to the exhaust system. The check engine light doesn't turns on, and with my OBD code reader i cannot read any fault codes.

Any help would be much appreciated.

Peter

 

[Grey Area]

Do you have any live diagnostics data? I've heard it's very helpful for diagnosing kompressor problems.

HERE is a link to thread that covers a fair few basic problems with the supercharger not kicking in. Hope it helps.

edit: HERE is another potentially useful thread.