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 20° ±2° BTDC. If not, the base timing of 10° BTDC should be adjusted accordingly.PERFORMANCE CHARTS
Chart Condition No. 1 No start or stall after start. No. 2 "Check Engine" light on - No codes set. No. 3 "Check Engine" light inoperative. No. 4 Fuel system diagnosis. No. 5 Poor performance. No. 6 Injector system diagnosis. No. 7 EGR diagnosis. No. 8 AIR management diagnosis. No. 9 Canister purge control diagnosis. No. 10 No cruise control. No. 11a Fuel Data display blank. No. 11b Fuel Data display incorrect (not blank). No. 12 Diagnostic display. No. 13 Improper idle speed. No. 14 Oxygen sensor test. No. 15 Improper coolant temperature operation. No. 16 TCC electrical test.