The mass air flow sensor measures the amount of air entering the engine to determine how much more gasoline is needed in each cylinder to help maintain the proper fuel air ratio. A bad MAF sensor results in a wide variety of problems with the engine.
One indication of a bad MAF sensor is that the engine may have trouble starting or turning over. A bad MAF sensor can also cause low gas mileage, engine stalling or jerking during acceleration. One of the most obvious indicators is the check engine light flashing, which happens after the problem has become significantly worse. However, since many problems that can cause this to happen, the car's computer must be analyzed to determine the actual problem.
Either a mechanic can analyze the car's computer or the owner can do it with the purchase of a device that plugs directly into the car. The owner of the car must then compare the code extracted from the computer to a book supplied with the device that lists the issue corresponding to this code. In order to repair a moderately performing MAF sensor, the sensor must be removed and cleaned with alcohol or a special cleaning fluid. Then it must be completely air dried before reinstalling.