Sensor/System Checks

Check Heated Oxygen Sensors (HO2S). The HO2S should respond quickly to different throttle positions. If they do not, inspect the HO2S for silicone or other contaminates from fuel or the use of improper RTV sealant. The sensors may have a white, powdery coating and result in a high but false signal voltage rich exhaust indication. The PCM will then reduce the amount of fuel delivered to the engine causing a severe driveability problem.
Check for an Engine Coolant Temperature (ECT) sensor that has shifted in value. See TEMPERATURE VS RESISTANCE table.
Check for proper operation of the Manifold Absolute Pressure (MAP) sensor. See DIAGNOSTIC TROUBLE CODE DEFINITIONS under DIAGNOSTIC TESTS in SELF-DIAGNOSTICS - 2.2L SATURN "L" SERIES article.
Check for proper operation of the Throttle Position (TP) sensor. See DIAGNOSTIC TROUBLE CODE DEFINITIONS under DIAGNOSTIC TESTS in SELF-DIAGNOSTICS - 2.2L SATURN "L" SERIES article.