1997 Mercedes Benz 280

JACQUIER

MEMBER
1997 MERCEDES BENZ 280

Engine Performance problem
1997 Mercedes Benz 280 128000 miles

1997 Mercedes Benz C280 Mass Airflow Sensor replaced because of codes P0171 and P0174. When I drive the car for 3 miles or more it hesitates and backfires. No codes will show up now. Once the car warms up it hesitates, backfires and stalls.

1 Reply

RASMATAZ

MECHANIC
75,992 POSTS

Hi there Jacquier and TY for the donation this is what keeps the site going

Its probably still running lean-might also be caused by the following:

* Low fuel pressure due to a weak pump or leaky fuel pressure regulator. (Use a fuel pressure gauge to check fuel pressure at idle)

* Dirty fuel injectors. (Try cleaning the injectors)

* Vacuum leaks at the intake manifold, vacuum hose connections or throttle body. (Use a vacuum gauge to check for low intake vacuum)

* Leaky EGR valve. (Check operation of EGR valve)

* Leaky PCV Valve or hose. (Check valve and hose connections)

* Dirty or defective Mass Airflow Sensor (MAF). (Try cleaning the MAF sensor wires or filament with aerosol electronics cleaner. Do NOT use anything else to clean the sensor, and do not touch the sensor wires)