Possible Causes & Corrections

WARNING: This page is about a different car, the 2003 Saturn Vue. However, it is still accessible from the selected car via links, so may be relevant.

Check for the following items:

Using scan tool, check misfire counts.
Verify Torque Converter Clutch (TCC) operation and customer understanding of TCC.
Verify proper A/C clutch operation.
Using scan tool, monitor fuel trim values for system running lean.
Using scan tool, monitor fuel trim values for system running rich.
Generator output voltage.
Vacuum lines for kinks or leaks.
Fuel pressure. See FUEL SYSTEMS in BASIC DIAGNOSTIC PROCEDURES - 2.2L & 3.0L VUE article.
Spark plugs for cranks, wear, burned or heavy deposits on electrodes.
Fuel quality.