There are two main types of mass air flow sensors in automotiveengines, the vane meter and the hot wire. The vane meter is an olderstyle. It measures the amount of airwith a spring loaded flap attached to a resistor. The vane meter is not used as often as thehot wire because it restricts airflow, the moving parts wear easier, andfinding a space to mount it is difficult. On the other hand, the hot wire stylehas minimal airflow resistance, it’s smaller, it has no moving parts that wear,and it responds very quickly to changes in air flow. So, basically the hot wire is a skinnier,smarter version of the vane meter.
If your Mass Air Flow Sensor is malfunctioning your car mayidle erratically, run lean, try to stall, and the throttle could decrease athighway speeds. If you have a digitalscanner you can make sure that your MAF is to blame by hooking the scanner upto the housing circuit and checking for codes. In some cases the sensor is justdirty and needs to be cleaned, but more commonly the part is broken. MAFs are rarely repairable and a new one willrun you a couple hundred dollars.
