DTC P2279: Air Intake Leak Detected: Description
WARNING: This page is about a different car, the 2003 GMC Sierra, 2003 GMC Cab & Chassis Sierra, 2003 Chevrolet Silverado, and 2003 Chevrolet Cab & Chassis Silverado. However, it is still accessible from the selected car via links, so may be relevant.
The Mass Airflow (MAF) sensor measures the amount of air entering the engine during a given time. The Engine Control Module (ECM) uses the MAF sensor information to monitor Exhaust Gas Recirculation (EGR) flow rate. A large quantity of air entering the engine indicates an acceleration or high load condition while a small quantity of air indicates a deceleration or idle condition. The ECM has the ability to detect an air intake leak by using the MAF sensor and the EGR control pressure sensor.