2004 C240 4Matic stalling when cold, overall power loss
I am having the following issues with a 2004 C240 4 Matic:
- every morning (or when the engine gets cold), if I start driving or just rev the engine in park, the car stalls really bad (sounds like a misfire) once or twice and then it is fine. I doubt it is a matter of the car, coils, spark plugs etc heating up as this happens right after starting it and disappears as soon as I rev the engine over 3-4000 RPMs. No misfire codes are stored in the vehicle's computer and changing the spark plugs did not solve the problem
- overall I notice a loss of power, like the gas pedal is "heavy". Every 200 miles or so the following codes come up: P0171, P0174 and P0101. The first two are lean codes and the last seems to be a MAF. Could all of the above problems be related to the MAF?
Any help would be greatly appreciated, thanks guys!
I had a similar issue with my 2001 C320 around 95,000 miles. It only happened when the car was cold and it would feel like the car was about to stall and then would jump back to life and take off. I replaced my MAF and haven't had any problems since.
I also just replaced my crankshaft position sensor (at 105,000 miles) but that was causing the car to completely shut down and not restart until cool so it sounds more like a MAF problem then CPS.
Drives: late 2009 CLK 350 Coupe Elegance, '65 Jaguar S Type wires
P0171 = System too Lean (Bank 1)
P0174 = System too Lean (Bank 2)
P0101 = Mass or Volume Circuit Range Performance Problem
This is undoubtedly the MAF. You can try cleaning it but likely need a new one.
Please make sure you get the correct OE MAF. The MB part number is on the black plastic cover. There are VW/Audi MAFs out there on the internet that look identical & fit but won't work properly with a Benz - different calibration.
Buy from a reputable Benz spares supplier - You don't need to be ripped off by a dealer.