IST1 - Check Base Timing

^ Connect Rotunda NGS Scan Tool 007-00500.

^ Start the engine and run until at normal operating temperature.

^ All electrical loads off.

^ Connect Rotunda Inductive Timing Light 059-00005, or equivalent.

^ Run the engine at 2000 rpm for 2 minutes.

^ Accelerate the engine 2-3 times.

^ Run the engine at idle for 1 minute.

^ Select ENGINE.

^ Select WORK SUPPORT

^ Select IAC VALVE ADJUST

^ Press TRIGGER.

^ Accelerate the engine to 2000-3000 rpm 2-3 times, then run at idle.

^ Check timing.

NOTE: If NGS Scan Tool is not available, disconnect the Idle Air Control (lAC) solenoid connector, then check timing.

^ Is timing 15 degrees ± 2 degrees BTDC?

YES -- Go to IST2. IST2 - Check Idle Speed

NO -- ADJUST the timing by loosening the distributor bolt and turning the distributor housing. TIGHTEN the distributor bolt to 14-17 N.m (10-12 lb-ft).