ford focus mass air flow sensor problems

There are several symptoms of a bad MAF sensor, and not all of them are immediately obvious:

If you have a bad MAF sensor, the engine control module (ECM) cannot calculate fuel injection correctly, which can lead to larger issues with your vehicle. Acceleration might require a rich AFR, up to 12:1, while cruising requires a leaner AFR, sometimes as low as 22:1. The ideal AFR is 14.7:1 (14.7 pounds of air to 1.0 pounds of gasoline), but real-world AFR varies. Measuring air mass is critical in calculating how much fuel to add to achieve the correct air-fuel ratio (AFR). The mass air flow sensor measures the air mass flowing into the engine intake. If your vehicle is having performance issues, you may be experiencing one of the symptoms of a bad mass air flow sensor.

Several sensors and actuators come into play, such as the mass air fuel (MAF) sensor and fuel injectors, and just as with any other car part, these sensors and actuators can degrade over time. Modern electronic engine controls calculate the correct quantity of fuel for a given situation.

Ford focus mass air flow sensor problems