Operation CHARM: Car repair manuals for everyone.
Manuals through 2025 now available!

Our trusted friends have launched a new website named LEMON, which has newer manuals. It also contains all the CHARM manuals.

LEMON is the logical successor to CHARM, I recommend you try it!

Link: lemon-manuals.la

Ignition Timing: Testing and Inspection

NOTE: Base (initial) ignition timing is NOT adjustable on any engine. Do not attempt to adjust ignition timing by rotating the distributor.

All ignition timing functions are controlled by the powertrain control module (PCM). For additional information, refer to Powertrain Management/Computer and Control Systems/Powertrain Diagnostic Procedures
service for operation of the DRB Scan Tool.