Today I was driving on the motorway and when I hit full throttle in 5th and 6th gear the car was holding down and I noticed my A/F dropped till 10 and normally it is around 11.5,he didn't stutter but was really slow,but in first,second and 3th gear he feels normal,boost was always around 1.1 bar.
I suppose this is a bad MAF ?
I have no cell's...

 

Sounds like the ECU saw something it didn't like (probably knock) and opened the injectors wide open (hence the low AFR) and pulled timing (hence no power). That's Bosch motronic doing it's job.
Has the issue repeated itself? Might have been anything (vibration mistakenly picked up by the knock sensor, bad gas, etc.)
Note, the car generally runs strong with a bad MAF (it essentially goes carburated) though it idles poorly (and stalls under certain conditions). Some guys even pull their MAF at the drag strip to fully disable PSM.

 

Ok I will run the car later today and see what happens....

 

Also, have the OBD fault codes read. Just because there wasn't a CEL doesn't mean you didn't throw any codes.