Diagnostic Aids

Inspect for the following conditions:

• An incorrectly routed harness. Inspect the harness of the MAF sensor in order to verify that the harness is not routed too close to the ignition cassette, solenoids, relays or any motors.
• A skewed or stuck TP sensor.
• Any excessive deposits on the throttle plate or in the throttle bore.
• A low minimum air rate through the sensor bore may cause this DTC to set at idle or during deceleration. Inspect for any vacuum leaks downstream of the MAF sensor.
• A Wide Open Throttle (WOT) acceleration from a stop should cause the MAF sensor g/s display on scan tool to increase rapidly. This increase should be from 4-7 g/s at idle to 190 g/s or more at the time of the 1-2 shift. If increase is not observed, inspect for a restriction in the induction system or exhaust system.
• The Barometric Pressure (BARO) that is used in order to calculate the predicted MAF value is initially based on MAP sensor at key ON. When engine is running, the Manifold Air Pressure (MAP) sensor value is continually updated near WOT. A skewed MAP sensor will cause the calculated MAF value to be inaccurate. The value shown for the MAP sensor display varies with the altitude. With ignition on, and engine off, 103 kPa is the approximate value near sea level. This value will decrease by approximately 3 kPa for every 1000 ft. (305 meters) of altitude.
• High resistance on MAP sensor ground circuit can cause this DTC to set.
• Any loss of vacuum to MAP sensor can cause this DTC to set.

If the condition is intermittent, see INTERMITTENT CONDITIONS  under SELF-DIAGNOSTIC SYSTEM.