Additional Checks
WARNING: This page is about a different car, the 2003 Chevrolet Corvette. However, it is still accessible from the selected car via links, so may be relevant.
- Visually and physically check the vacuum hoses for splits, kinks, and proper connections and routing as shown on Vehicle Emission Control Information (VECI) label.
- Inspect the transmission Torque Converter Clutch (TCC) operation. The scan tool should indicate a RPM drop, when the system commands the TCC ON. See appropriate DIAGNOSIS article in TRANSMISSIONS.
- Inspect the exhaust system for a possible restriction. Inspect for the following:
- Inspect the exhaust system for damaged or collapsed pipes.
- Inspect the mufflers for heat distress or possible internal failure.
- Inspect for possible plugged catalytic converters. See RESTRICTED EXHAUST .
- Electromagnetic Interference (EMI) on the reference circuit can cause an engine miss condition. A scan tool can usually detect EMI by monitoring the engine RPM. A sudden increase in RPM with little change in actual engine RPM change indicates EMI is present. Inspect for high voltage components, near ignition control circuits, if a condition exists.
- Inspect the Park Neutral Position (PNP) switch circuit.
- Inspect the intake and the exhaust manifold passages for casting flash.
- inspect the brake system for dragging or improper operation. See appropriate article in BRAKES. Verify that the vehicle operator does not drive with a foot on the brake pedal.