Diagnostic Aids

Inspect for the following conditions:

1. An incorrectly routed harness. Inspect the harness of the MAF sensor in order to verify that it is not routed too close to the following components:
   • The secondary ignition wires or coils.
   • Any solenoids.
   • Any relays.
   • Any motors.
2. The throttle plate for sticking, or for deposits on the throttle plate or in the throttle bore.
3. 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.
4. A wide open throttle acceleration from a stop should cause the MAF sensor g/s display on the scan tool to increase rapidly. This increase should be from 6-12 g/s at idle to 130 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.
5. The barometric pressure that is used in order to calculate the predicted mass air flow value is initially based on the MAP sensor at key ON. When the engine is running, the MAP sensor value is continually updated near wide open throttle. A skewed MAP sensor will cause the calculated mass air flow value to be inaccurate. 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.
6. A high resistance on the ground circuit of the MAP sensor may cause this DTC to set.
7. Any loss of vacuum to the MAP sensor may cause this DTC to set.
8. A high resistance in the ignition voltage circuit of the MAF sensor may cause this DTC to set.

Condition may be related to aftermarket accessories. If the condition is intermittent, see INTERMITTENT CONDITIONS  under SELF-DIAGNOSTIC SYSTEM.