Mass air flow sensor (Engine management system - EDC)

Mass air flow sensor

The mass air flow sensor is located in the inlet pipe from the air cleaner. The mass air flow is determined from the cooling effect of inlet air flowing over a Hot Film sensor. This signal is fed back to the ECM where it is used to monitor the recirculation of exhaust gases. Increase in the exhaust gas recirculation reduces the amount of intake air being drawn into the system, thereby reducing the cooling effect of Hot Film resistor.

Vehicle speed sensor

The vehicle speed sensor is located on the top of the differential housing. The vehicle speed sensor is driven by a shaft from the final drive gear where it is converted into an electrical signal proportional to road speed. The output from the vehicle speed sensor is used to drive the speedometer in addition to providing a signal to the ECM. The ECM uses this signal to provide active surge damping and adjust idle stabilisation and the quantity of fuel being delivered to injectors.