Best way is to perform diagnostics with a scan tool and DVOM. Easiest way is to replace the MAF and hope that is the cause and nothing else.
Try this first.
Diagnostic Aids
Ensure MAF sensor harness is not routed too close to secondary ignition wires or coils, solenoids, relays, or motors. Check throttle plate for sticking, or deposits on throttle plate or throttle bore. A low minimum air rate through the sensor bore may
cause this DTC to set at idle or during deceleration. Check for any vacuum leaks downstream of MAF sensor. A Wide Open Throttle (WOT) acceleration from a stop should cause MAF sensor grams/second display on scan tool to increase rapidly. This increase should be from 6-12 grams/second at idle to 130 grams/second or more at
time of the 1-2 shift. If increase is not observed, check for a restriction in the induction system or exhaust system.
The Barometric Pressure (BARO) sensor is used in order to calculate the predicted MAF value is initially based on MAP sensor at key on. When engine is running, 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 MAP sensor display varies with altitude. With ignition on, and engine off, 103 kPa is the approximate value near sea level. This value will decrease by about 3 kPa for every 1000 feet of altitude. A high resistance on the ground circuit of MAP sensor may cause this DTC to set. Any loss of vacuum to MAP sensor may cause this DTC to set. A high resistance in ignition voltage circuit of MAF sensor may cause this DTC to set.
Saturday, September 8th, 2012 AT 6:35 PM