Diagnostic Aids

• Inspect the harness of the MAF sensor to verify that it is not routed too close to the secondary ignition wires/coils, solenoids, relays, or motors.
• A low minimum air rate through the sensor bore at idle or during deceleration may cause this DTC to set. Inspect for any deposits on the throttle plate or in the throttle bore or a vacuum leak downstream of the MAF sensor.
• Inspect for any contamination or debris on the sensing elements of the MAF sensor.
• Inspect the air induction system for any water intrusion. Any water that reaches the MAF sensor will skew the sensor and may cause this DTC to set.
• A wide open throttle acceleration from a stop should cause the MAF sensor parameter on the scan tool to increase rapidly. This increase should be from 7-12 g/s at idle to 150 g/s or more at the time of the 1-2 shift. If the increase is not observed, inspect for a restriction in the induction system or the exhaust system.
• Inspect for a skewed or stuck ECT sensor.
• Inspect for a skewed or stuck TP sensor.
• A high resistance of 15 ohms or more on the ignition 1 voltage circuit may cause this DTC to set. A high resistance may cause a driveability concern before this DTC sets.
• The barometric pressure that is used in order to calculate the predicted mass airflow value is initially based on the MAP sensor at key ON. When the engine is running the BARO sensor value is continually updated near wide open throttle. A skewed MAP sensor will cause the calculated mass airflow value to be inaccurate and may result in a no start condition. The value shown for the MAP sensor display varies with the altitude. With the ignition ON and the engine OFF, 103 kPa is the approximate value near sea level. This value will decrease by approximately 3 kPa for every 1000 feet (305 meters) of altitude.
• A high resistance on the low reference circuit of the MAP sensor may cause this DTC to set.

If the problem is intermittent, See INTERMITTENT CONDITIONS  under SELF-DIAGNOSTIC SYSTEM.