Q: What is the responsibility of the Mass Air Flow (MAF) sensor?
A: The Mass Air Flow (MAF) sensor is responsible for measuring the amount of air that enters the engine. It is a hot film type sensor that calculates airflow rate based on the power required to maintain the sensing elements at a fixed temperature above ambient temperature. The MAF sensor has a switched battery feed, a ground, a signal circuit, and a signal return circuit. The PCM reads the voltage signal from the MAF sensor and calculates airflow based on the changes in current draw. To test the MAF sensor, visually check the connector for security and cleanliness, tap on the sensor and wiggle the wires to check for any changes in idle speed, and backprobe the sensor connector using a DVOM set to the Hertz scale to check for a frequency swing when air is blown across the wire. If the sensor is faulty, it may need to be replaced. The removal and installation process involves removing the intake air duct, detaching the MAF sensor electrical connector, removing the mounting screws, and then reversing the procedure to install the new sensor.