Ignition Timing

IGNITION TIMING SPECIFICATIONS ⁽¹⁾

Application

Man. Trans.

Auto. Trans.

Metro

⁽²⁾ 4-6 @ 750-850

⁽²⁾ 4-6 @ 800-900

⁽¹⁾	If specification differs from emission label, use specification listed on emission label.

⁽²⁾	With jumper wire installed between 6-pin duty check data link connector terminals "D" (Black wire) and "E" (Purple/Green wire), located behind left strut tower.

Warm engine to normal operating temperature. Turn engine off but keep ignition on for 5 seconds. Restart engine, and raise engine speed to 2000 RPM for 5 minutes. Return to idle. Ensure transaxle is in Neutral (M/T) or Park (A/T). Ensure parking brake is fully applied. Ensure all accessories are off and idle speed is within specification. Adjust idle speed first if it is not within specification. See IDLE SPEED under IDLE SPEED & MIXTURE.
Connect timing light to No. 1 spark plug wire. Remove cap from duty check 6-pin Data Link Connector (DLC), located in rear corner of engine compartment near left strut tower. Connect a fused jumper wire between terminals No. 4/D (Black/Blue wire) and No. 5/E (Purple/Green wire) of duty check DLC. See Fig 1 .
Check timing mark on crankshaft pulley with timing marks on timing belt cover. Notch on crankshaft pulley should line up at 4-6 degrees BTDC on timing indicator. Ignition timing must be within specification. See IGNITION TIMING SPECIFICATIONS .
If ignition timing is not as specified, loosen distributor hold-down flange bolts, and rotate distributor to obtain correct ignition timing. Tighten distributor hold-down flange bolts to 11 ft. lbs. (15 N.m). Recheck ignition timing. Turn engine off. Remove jumper wire, and install cap on duty check DLC. Remove test equipment.

Fig 1: Identifying Duty Check DLC Terminals (Metro)

Courtesy of GENERAL MOTORS CORP.