Diagnostic Aids

WARNING: This page is about a different car, the 2002 Oldsmobile Intrigue and 2002 Oldsmobile Aurora. However, it is still accessible from the selected car via links, so may be relevant.

NOTE: Use the Connector Test Adapter Kit (J-35616-A) for any test that requires probing the PCM harness connectors, electrical center fuse/relay cavities, component terminals and component harness connector. Using this kit will prevent damage caused by improper probing of connector terminals.

Using scan tool, perform CKP system variation learn procedure. See CRANKSHAFT POSITION SENSOR SYSTEM VARIATION LEARN PROCEDURE under PROGRAMMING. Ensure all connections are clean and properly tightened. A damaged serpentine belt or belt driven accessory can cause engine load variations sufficient to set a misfire DTC. Check fuel pressure. See appropriate BASIC DIAGNOSTIC PROCEDURES article. A malfunctioning fuel pump, a plugged filter, or a malfunctioning fuel system pressure regulator will contribute to a lean condition. Performing fuel injector coil test. See FUEL SYSTEMS in appropriate SYSTEM & COMPONENT TESTING article. Check for contaminated fuel. Excessive open loop operation caused by extended idling or short trip driving may leave deposits on heated oxygen sensors. Deposits cause oxygen sensors to respond slowly to exhaust oxygen content, affecting fuel control and causing a misfire to be indicated at idle. This condition is not permanent. In order to determine if this condition is causing DTC P0300 to be set, review FREEZE FRAME/FAILURE RECORDS for DTC P0300. If DTC P0300 occurs at high engine speeds, the condition described above did not cause DTC P0300 to set. If DTC P0300 occurs at idle or very low engine speeds and at engine coolant temperatures less than 176°F (80°C), the condition described is very likely the cause of the DTC P0300 being set. The deposits on the heated oxygen sensors can be eliminated by operating vehicle fully warm at mass airflow more than 15 grams/sec. DTC may set if vehicle misfires while running out of fuel. If no misfire is currently present, but history counters indicate random misfire was once present, ask customer if vehicle has run out of fuel. If this is the case, no further repair may be necessary.