Ignition Timing: Adjustments
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Set timing at low idle and Before Top Dead Center, unless otherwise specified. Disconnect and plug distributor vacuum line, as equipped, at distributor.
1982-86 1.8L (112) FI, 2.5L (151), 4.3L (260), 5.0L (307) engines, ground diagnostic connector.
1982-86 2.0L (122) FI, 2.8L (173) FI, disconnect EST bypass connector (single connector, tan/black wire).
1981-90 all others W/carburetor, disconnect 4-wire connector at distributor.
Timing MUST be set to specifications on emission label, if different from setting listed. If "Check Engine" light comes on during procedure, remove ECM fuse to clear.