The mass air flow sensor, or MAF, controls the amount of fuel delivered through the injectors based on the volume of air entering the intake. If your vehicle is throwing a MAF code, replace it as soon as possible to ensure you get the best fuel mileage and performance.

It is common for this part to fail slowly, causing poor fuel mileage and hampered performance. When it fails completely, the vehicle will stutter and stall as it falls into a limp mode. A good way to check your MAF is unplugging the connector before starting your car, if it idles well (compared to a previous poor idle), your MAF needs replaced.