BMW - BOSCH MEVD17.2-MED17.1.1

MAF REMOVAL

MAF (Mass Air Flow)

The main function of the MAF sensor is to precisely measure the amount of air entering the engine. This information is critical to optimizing engine performance and controlling exhaust emissions. The ECU adjusts the fuel injection system and ignition timing using the data it receives from the MAF sensor. Thus, the engine operates efficiently and stably under different operating conditions (for example, acceleration, deceleration or idling).

WORKING PRINCIPLE OF MAF Sensor

MAF sensors generally come in two main types:

  • Hot Wire MAF Sensor:

    The hot wire MAF sensor measures air flow around a heated wire. The wire is maintained at a certain temperature, and as air flow increases, the temperature of the wire decreases. The amount of energy required to keep the temperature of the wire constant is a measure of air flow. This energy is transmitted to the ECU as an electrical signal.

  • Vane Meter (Vine Type) MAF Sensor:

    In this type of sensor, air flow moves a vane. The position of the fin determines the amount of air entering the engine. The movement of the vane is converted into an electrical signal by a mechanism such as a potentiometer and transmitted to the ECU.

COMPONENTS OF MAF (Mass Air Flow)

  • Air Ducts:
    • Inlet and Outlet Channels: These are the channels that bring air to the section where the air flow of the MAF sensor is measured and provide air exit. These channels regulate the flow of air through the sensor.
  • Precision Measuring Element:
    • Hot Wire: It is the most commonly used type. A wire or film is heated by an electric current, and air flow over it lowers the temperature of the wire. The energy required to keep the temperature of the wire constant is used as an indicator of the amount of air flow.
    • Platinum Film: A thin layer of film used in some modern sensors. The working principle is similar to hot wire.
  • Thermistor:

    A thermistor is a component that measures temperature. It monitors the temperature of the hot wire or film layer and detects temperature changes based on the amount of air flow.

  • Electronic Circuits:
    • Control Circuit: These are the circuits that process the signals coming from the sensitive measurement element and transmit these signals to the engine control unit (ECU).
    • Amplifier: A component that amplifies measured signals. This provides more accurate and reliable processing of signals.
  • Housing:

    It is the structure that contains and protects all components of the MAF sensor. It is usually made of plastic or metal, allowing the sensor to be mounted securely in the engine compartment.

  • Connection Connectors:

    These are the electrical connection points that connect the MAF sensor to the engine control unit. These connectors allow data from the sensor to be transmitted to the ECU.

  • Air Filter (Some Models):

    Some MAF sensors have an integrated air filter to protect the sensitive measuring elements inside the sensor. This filter prevents large particles from damaging the sensor.

  • Measurement Channels:

    These are channels that direct the air flow within the sensor so that the air can be measured accurately. These channels direct the air flow towards the measuring element and provide a stable measurement.

PROBLEMS OF MAF (Mass Air Flow)

  • Limp mode problem
  • Engine starting or stalling irregularly
  • Poor acceleration and low power
  • Increase in fuel consumption
  • Engine has difficulty starting or does not start at all
  • Malfunction light coming on (Check Engine Light)
  • Erratic Idle

NUOVOLTA SOLUTION OF MAF (Mass Air Flow)

  • Offical diagnostic tool must reset position the relevant module.
  • DTC codes should be read and removed with a diagnostic tool.
  • Apply the solution of the module related to NUOVOLTA.
  • Write the mod file to the ECU.
  • Check the dashboard and DTC logs. Take it for a test drive.
  • If all the checks are OK, it means the problem is solved.