Fixed Spark Mode Procedure
- Purpose of test is to verify proper adjustment of spark timing. Enter diagnostics and with code ".7.0" displayed on ECC panel, depress "Instant/Average" button on Fuel Data panel. Code ".9.5" should appear.
- With engine at normal operating temperature, idling at less than 900 RPM and transmission in "P" position, attach a timing light and observe ignition timing. Under these conditions, and with HEI operating properly (codes 23 and 25 not set), ignition timing should be within 18-22° BTDC. If not, the base timing of 10° BTDC should be adjusted accordingly.