Diagnostic Aids

WARNING: This page is about a different car, the 2002 Pontiac Grand Prix, 2002 Chevrolet Malibu, and 2002 Buick Century. However, it is still accessible from the selected car via links, so may be relevant.

Check for any of the following conditions:

An incorrectly routed harness. Inspect the MAF sensor harness in order to verify that the harness is not routed too close to the following components: The secondary ignition wires or coils, solenoids, relays or motors.
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 skewed or stuck TP sensor.
A skewed or stuck ECT sensor
A Wide Open Throttle (WOT) acceleration from a stop should cause the MAF sensor g/s display on the scan tool to increase rapidly. This increase should be from 4-7 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.
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 MAP sensor value is continually updated near WOT. A skewed MAP sensor will cause the calculated mass airflow 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 305 meters (1000 feet) of altitude.
High resistance on the ground circuit of the MAP sensor can cause this DTC to set.
Any loss of vacuum to the MAP sensor can cause this DTC to set.
High resistance on the ground circuit of the ECT sensor can cause this DTC to set.

Problem could also be caused by aftermarket accessories. If the condition is intermittent, refer to INTERMITTENT CONDITIONS under SELF-DIAGNOSTIC SYSTEM.