Diagnostic Aids

WARNING: This page is about a different car, the 2003 GMC Sierra, 2003 GMC Cab & Chassis Sierra, 2003 Chevrolet Silverado, and 2003 Chevrolet Cab & Chassis Silverado. However, it is still accessible from the selected car via links, so may be relevant.

Inspect for the following conditions:

Inspect the harness of the MAF sensor to verify that it is not routed too close to the following components:
- Any unmetered air - Any unmetered air that enters the engine downstream of the MAF sensor may cause this DTC to set.
- A sluggish or unresponsive MAF sensor - A short between the signal circuit of the MAF sensor and the signal circuit of the intake air temperature (IAT) sensor. This will cause the MAF sensor to have a very limited output voltage range.
- Any debris that may be blocking the sensing elements of the MAF sensor.
- Any water in the air induction system.
- The MAF display should increase from 42-50 g/s at idle to 420 g/s or more at the 2-3 shift during a Wide-Open Throttle (WOT) acceleration. If not, inspect for a restriction in the induction system or the exhaust system.
- If the condition is intermittent, see INTERMITTENT CONDITIONS under SELF-DIAGNOSTIC SYSTEM.