Diagnostic Aids
WARNING: This page is about a different car, the 2003 GMC Savana and 2003 Chevrolet Chevy Express. However, it is still accessible from the selected car via links, so may be relevant.
Check for one of the following:
- A loose or missing distributor hold down bolt.
- Loose CMP sensor causing a variance in the sensor signal.
- An incorrectly installed distributor - one tooth off in either advance or retard positions.
- A loose distributor rotor on the distributor shaft.
- Excessive free play in the timing chain and gear assembly.