W212 E250 Engine noise at low revs
 

Hi there guys,
I have the E250 Cdi W212 model.

I had taken the car in for a few minor issues to MB Melb and discovered they needed to change the ECU as it wouldnt accept the new firmware, l think injectors too (l think) then discocered a fault with some airflow sensor.

EVER since these changes from Aug the engine is LOUDER, and in the low rev range 1000-1800rpm, it makes a bearing noise. Hard to describe it but if you put a manual car in 4th gear and accelerate at 20km/h (clearly wrong gear for that speed) thats the kind of noise it makes. If you drive it in a city carpark where it echoes its like a tinny, pinging noise, it sounds WRONG for a Merc.
I took it in yesterday and they have booked it in for later this week but l'm finding it hard dealing with MB as they almost pretend NOT to hear it, oh its normal. Its NOT normal. It started doing this since my last visit to Mercedes. Its a MAJOR embaresment driving past for people to hear.

Could this be an injector even though they replaced them ?

Another issue is lately the car doesnt realise it needs to change gears. It seems to get stuck at 2600 rpm 95km/h and almost doesnt realise that it has 7th gear to slide into. To fix this l have to increase speed more for it then to drop into 7th.

Not sure whats going on but this is NOT what a $100k Mercedes ought to be doing.

Has anyone faced these same issues ? My 20 yo Mazda with a worn engine does these things- NOT expecting a new MERCEDES.

THANKS

Yes the v6 engines have a fault on the Numba 1 cylinder Conrod bearing apparently it's a factory fault it's got to be done free off charge by mb on all the v6 engine code 642 have got the fault with the Numba 1 cylinder crankshaft bearing