Possible Causes & Corrections

WARNING: This page does not describe the selected car, but rather 34 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.

Check the following items:

Check exhaust system for restrictions, such as a damaged or collapsed pipe, muffler or catalytic converter. See EXHAUST SYSTEM BACKPRESSURE under MECHANICAL INSPECTION in appropriate BASIC DIAGNOSTIC PROCEDURES article.
Check engine compression. Check for incorrect valve timing, bent push rods, broken valve springs or worn camshaft lobes.
Check fuel injectors. Perform injector balance test. See FUEL INJECTOR BALANCE TEST under FUEL SYSTEMS in appropriate SYSTEM & COMPONENT TESTING article.
Check fuel system for incorrect fuel pressure. See BASIC FUEL SYSTEM CHECKS in appropriate BASIC DIAGNOSTIC PROCEDURES article.
Check for items that cause the engine to run rich, or lean.
Check transmission shift solenoid system and Torque Converter Clutch (TCC) system for proper operation.
Using Spark Tester (J-26792), check for adequate spark output.
Ensure correct initial ignition timing.
Check Knock Sensor (KS) system for excessive retard.
Check air filter and fuel filter. Replace if necessary.
Check for poor fuel quality or water-contaminated fuel.
Check fuel injector wires for short to ground at air cleaner.
Check PCM grounds. Ensure they are clean, tight and properly located.
Ensure EGR valve is not stuck open.
Check for proper operation of the Transmission Fluid Pressure (TFP) manual valve switch.
Check charging system output. Repair if output is less than 9 volts or greater than 16 volts.
Check A/C for proper operation.
Check for conditions that cause the engine torque management system to reduce engine power.