Update: Cleaning the MAF did not resolve the check engine code. Stay tuned to "Driver's Ed" to see if cleaning the throttle body does the trick!
Mass air flow, or MAF, sensors measure the amount of air and the density of the air coming into your engine. The computer uses that information to adjust the spark and the amount of fuel.
When the MAF sensor is dirty or faulty, you could see a loss in power, a loss in fuel economy and even the check engine light come on.
Find out more about the MAF sensor and how to clean it in the "Driver's Ed" segment above.