Mass Air Flow Meter (MAF)

Mass Air Flow Meter (MAF)

The mass air flow (MAF) sensor supplies the engine control module (ECM) with a signal describing the intake air mass.

This information is for instance used to:
- Regulate fuel/air conditions
- Regulate emission
- Calculate torque.

The MAF sensor consists of a plastic housing containing a connector, electronic circuitry and an aluminum heat sink. The MAF sensor measuring device is a heated film mounted in a pipe which is cooled by the intake air to the engine.

The heated film consists of four resistors. The MAF sensor is supplied with battery voltage and has separate power and signal ground points. The sensor signal varies from 0 V to 5 V, depending on the air mass. Voltage increases with air flow.

The ECM will adopt substitute (limp home) values if the MAF sensor signal is missing or faulty.

The MAF sensor is located between the air cleaner cover and the intake air hose.