Description
The Air Flow Sensor or Mass Airflow Sensor (MAF) is one of the
components of an electronic fuel injection system and is found in many of modern
vehicles. Most mass air flow sensors are one piece hermetically sealed units with no
moving components.
Purpose
The Mass Air Flow sensor is used to measure (actually weight) the amount of
air entering the engine. This measurement is used by the engine computer or ECM to
calculate proper amount of fuel injected into the cylinders in order to provide optimum
combustion and low emissions.
Maintenance Tips/Suggestions
BMW 330 (E46) Mass air flow sensor requires no
regular maintenance. On mass air flow sensors with a sense wire, this wire can become
contaminated with dust particles. These particles can be removed with automotive
solvents that are safe for the use on mass air flow sensors. BMW 330 (E46) mass air
flow sensors are commonly misdiagnosed. Before replacing the mass air flow sensor
check for air leaks in the connecting air ducts and intake manifold. These leaks can cause
similar symptoms as a malfunctioning mass air flow sensor.
Failure symptoms
Problems with Mass Air Flow sensors are common. Bad or
contaminated BMW 330 (E46) Mass Air Flow sensor can possibly cause a wide range
of various vehicle drivability problems such as stalling, especially when the engine is
cold, misfiring, poor acceleration, etc. In addition, a problem with the Mass Air Flow
sensor often causes the "check engine" or "service engine soon" light in the vehicle
instrument panel to illuminate.
AKA
MAF, Air Flow Meter
Location
The BMW 330 (E46) Mass Air Flow sensor is usually installed in the intake
air duct between the air filter and the throttle body mounted on the intake manifold.
Some mass air flow sensors are mounted directly to the throttle body.
Disclaimer
Depending on the year and options your BMW 330 (E46) has, the
above information may not apply. Consult with a professional automotive
technician or manufacturer for specifics on your BMW 330 (E46)
