Code p0101 maf sensor S203 2001

[froggiegit]

Been getting an endless problem for about 18 months with the management light coming on and indicating P0101 and maf sensor problems
I've changed that several times firstly with pattern ones and finally with a genuine one. Still the light comes on.
Also changed the map sensor, the cam position sensor on top the engine and the cam magnet sensor at the front of the engine with genuine mercedes parts.
Also had the air pipes beneath the airbox and rear of the engine changed.
But frustrating because none of that has solved the problem and light still comes on. Car runs well - better when I turn the management light out
Any suggestions please?

 

[Auto-mobile]

Clean the throttle body.

 

[froggiegit]

Thanks I'll try that later today

 

[froggiegit]

Cleaned the throttle body but discovered that the 'O' ring between the cover and the maf sensor was broken so this could be letting through unmetered air which could be the cause of my problem. Put it back together but forgot to measure the dimensions of the 'O' ring! Derr!

 

[Auto-mobile]

You should be able to get it from Mercedes, if it is between the engine and airmass then yes it could make the car run lean.

 

[froggiegit]

Thanks for your advice auto-mobile. Since cleaning the throttle body I've had a week without the engine management light coming on. Guess that was the problem all along. Got a replacement O ring on order but guess the existing one isn't leaking despite it's state. Car runs better than ever