How to diagnose a faulty mass air flow sensor

MAF) and to quickly know if it is defective. Mass air flow sensor testing with a multimeter without dismantling. Box titled Mass Air Flow Sensor Tests on the right of this page. This is the second from the top box.MAF) sensor measures the volume of air entering the engine so the Engine Control Unit (ECU) can calculate how much gasoline the fuel injectors should deliver to each cylinder in order to create the proper fuel-air ratio.

Sometimes, however, a malfunction in this little instrument can lead to big problems, usually resulting in very poor engine performance.Mass airflow sensor problems can cause a variety of symptoms from the annoying to the must repair. We'll discuss these in-depth on this page.

Mass air flow sensor (MAF) testing without dismantling

The faulty mass airflow sensor and how to fix the problem written by: nandy A vehicles MAF or mass airflow sensor, is the element that measures the density and flow of the air passing in to the combustion section.It assists the vehicles computer activate the air ratio to fuel.The first step in diagnosing a faulty MAF sensor is to perform my favorite test—the tap test. Using a screwdriver, lightly tap on the sensor while the engine is running, noting any changes in engine rpm or idle quality with each tap. A bad mass air flow sensor in a vehicle makes starting difficult and affects the performance of the engine because he engine-control unit uses data from the MAF sensor to balance the fuel ratio the injectors deliver to the engine.

A bad sensor returns a significantly different temperature than that of the engine coolant when read using a scan tool set to temperature.