Hard Failures
WARNING: This page is about a different car, the 1997 Pontiac Bonneville, 1997 Oldsmobile Regency, 1997 Oldsmobile LSS, 1997 Oldsmobile Eighty-Eight, and 1997 Buick LeSabre. However, it is still accessible from the selected car via links, so may be relevant.
Most hard failures cause MIL to illuminate and remain on until malfunction is repaired. If MIL comes on and remains on (light may flash) during vehicle operation, cause of malfunction must be determined. See DIAGNOSTIC PROCEDURE .
If a sensor fails, PCM/VCM will use a substitute value in its calculations to continue engine operation. In this condition, vehicle is functional, but it will most likely display degraded driveability.