Ignition Timing

With transmission in Neutral or Park, start engine and warm to normal operating temperature. Ensure CHECK ENGINE light is off. Turn engine and all accessories off.
Connect jumper wire between ALDL diagnostic connector terminals No. 1 and 3. The White, 3-pin ALDL connector is located behind right side of instrument panel. See Fig 1 . Connect timing light to No. 1 spark plug wire. Start engine.
Check ignition timing. See IGNITION TIMING table. Increase engine speed to 1500-2000 RPM to read timing (if necessary).
Adjust timing by loosening distributor hold-down bolt and turning distributor. Tighten distributor hold-down bolt to 17 ft. lbs. (24 N.m). Recheck timing. Remove jumper wire from ALDL connector and ensure CHECK ENGINE light is off. Idle speed is automatically controlled by ECM.

Fig 1: Locating ALDL Diagnostic Connector

Courtesy of ISUZU MOTOR CO.

IGNITION TIMING (Degrees BTDC @ RPM)

Application

Base Timing

Impulse & Stylus

⁽¹⁾ 9-11

⁽¹⁾	With jumper wire installed in ALDL diagnostic connector, located behind right side of instrument panel. Increase engine speed to 1500-2000 RPM to read timing (if necessary).