Non-EEC Engines

Place transmission in "P" or "N" and place air conditioner and heater in "OFF" position. Remove vacuum hoses at vacuum advance connection on distributor and plug hoses.
Connect inductive timing light and tachometer. If vehicle is equipped with barometric pressure switch, disconnect it from the ignition module and put a jumper wire across connector pins at ignition module.
If equipped with MCU (Microprocessor Control Unit), disconnect MCU wire harness at ignition module and place jumper wire across connector pins at ignition module.
Start engine and allow it to reach normal operating temperature. With engine at timing RPM, check and or adjust ignition timing to specifications.
Unplug and reconnect hoses, remove jumper wires from barometric pressure switch and MCU, and reconnect wires.

Ignition Timing Specifications (Degrees BTDC @ RPM)

Application

Man. Trans.

Auto. Trans.

4.2L

Federal

.....

8@800

Calif.

.....

12@800

5.0L

12@800

8@800

5.8L

.....

⁽¹⁾8@600

⁽¹⁾	Calibration number 2-24P-R10 is 12@600.