Hello all, We have a merc in our garage that is a sort of a dizaster at that stage. Last weak another came in with same symptoms so there have to be a solution that I just can't find. Tried almost everything. If anyone had similar problem I would apreciated any coments.

Mercedes 211.042 - 2003 year , 200 Kompresor

Selfadaptation goes pass +1 every time. Once reset to zero goes up slowly straight away
Fault code 2029-001 system rich and self adaptation faults
Lambda 1 oscilating 950mV- 1050mV at idle
Eliminated all leaks thru overpressure test, replaced breather pipes. Intake system is holding the pressure when system blocked at air mass meter using merc tool.
Have donor car that works fine (checked values for lambda and emissions). Swapped air mass meter / fuel rail.
Lambda 1 and 2 brand new installed.
Checked wires from lambda 1 to ecu for extra resistance, nothing found. Resistance around 0.1 Ohm at all wires
Blocked off fuel tank breather, still no difference to lambda reading. Valve for breather clicking.
2nd air valve swapped over , no difference
Fault for Lambda control keeps coming back upstream of TWC 2058-001
Replaced full identity from donor (ecu/ezs/lock) lambda went up to 1500. After testdrive it stayed around 1400, so assumed faulty ECU
Replaced ECU programmed online and it was ok for around 3 days. Gave car back to the customer. He rang next day that engine light is back ON, Checked all values again and self adaptation +1.9, and Lambda 1 again around 990mV !!!!!!!!!!
Cleaned all intake system by spraying BG stuff for system cleaning in case something enriches the mixture from inside - made no difference

 

this should be just air mass. after u change it or swap it u need to reset the self adaption w DAS scanner. the launch is also good for the reset but can't teach the throttle body. it will say in the actual values: throttle learned: yes/no
the air mass actual value cannot exceed the 1.02Volt. the new one is 1.00V. the 1.03V is gonna set the engine light.

 

welll thats what you would think.... I have stardiagnosis w3. selfadaptation was reset several times - no difference every time it was done. we swapped compresor and seems ok now !!!!