Diagnostic Aids
WARNING: This page does not describe the selected car, but rather 33 other vehicles, including the 2002 Saturn Vue, 2002 Pontiac Montana, 2002 Pontiac Aztek, 2002 Oldsmobile Silhouette, and 2002 Oldsmobile Bravada. However, it is still accessible from the selected car via links, so may be relevant.
Inspect for the following conditions:
- The Mass Airflow (MAF) is compared to a calculated MAF based upon the Manifold Absolute Pressure (MAP), the Throttle Position (TP), and the engine RPM. A skewed or unresponsive MAP sensor at key ON will cause the predicted airflow value to be inaccurate. Compare the MAP and TP readings to that of a known good vehicle.
- Inspect for a faulty Engine Coolant Temperature (ECT) sensor. Use a scan tool in order to compare the ECT with the Intake Air Temperature (IAT) on a completely cooled engine. The ECT should be within 5°F (3°C) of the IAT.
- For an intermittent condition, diagnose by symptom. See SYMPTOMS (GASOLINE) in TROUBLE SHOOTING - NO CODES - TRUCKS article.