Hello, can someone share what are the symptoms of bad MAF sensor? The car is E50 AMG,no error codes.

If you have bad MAF, will forcing "bad performance/little bit playing in low ideal/bad fuel consumption"..!

try to diagnose the car first, MAF is soo sensitive for "RPM ideal range/proper mixture/stable performance",,

that will directly affect to the fuel trim & functional signal of O2 sensors..!!

ZAYED,,

Unstable idle could be the result of:
1- Dirty/bad MAF.
2- Vacuum leak.
3- Old spark plugs/wires.
4- Clogged/bad EGR system (the valve could be stuck partly open while idle)
5- Bad O2 sensors.
6- Partly clogged catalytic convertors, since it's only noticeable on idle and exhaust pressure is low.
7- Valve covers leaking into the plugs.
8- A problem in the fuel system (pump, filter, injectors....)
9- Carbon build-up causes the valves not to close properly.
I can't help you precisely, but these engines are a PITB when it comes to diagnosing rough idle/misfire.
I'm diagnosing the same issue, drove me crazy.

Motor filled with smoke, no leakage from anywhere,throttle is very clean,i give up and remain a problem.

Cyl. 1 and 2 also is smooth running
but the picture has not come out,(left all cylinders)at a sharp turn to the right car stopped for a second as if out of fuel ( only a right turn )?

If fuel trim is OK, prefer to check MAF & TB..!,

if you replace any of them, and those issues still remain, afraid your ECU went away, which i hope NOT..!!

ZAYED,,

It's in another MAF,I traded and O2 sensors,the problem remains on the left bank,self adaptations it's not ok

Try to check if there are any leak around the MAF, or "8" O-rings in intake manifold,

also position sensor in the TB may NOT reads the air pressure properly, this also could cause same your issue,

i know this is some kind of Hard job on M119,,

little bit patient will solve this mystery..?!?

ZAYED,,

Thanks I'll check the O-rings,everything about the maf sensor is verified!

Check the TB as well, or if you can swap it with another one it will be better..

ZAYED,,

Тoday I tried to spray and get the same thing as this video.O-rings?I've experienced the same thing

Good catch..

ZAYED,,

Cold start

Тhis is a problem that occurs when a cold start today and warmed car.When the car is cold I can't touch the accelerator , dies out , bounce ..

Did you replace the O-rings..?

ZAYED,,

With orders are still waiting for them.

Need to pull out the intake to check clearly, if leaks not reaches the TB housing or gasket as well..!?!

ZAYED,,

I will remove intake manifold and i'll checking everything