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V8 Ignition Timing

  1. Set parking brake, block drive wheels and place transmission in Neutral or Park. Warm engine to normal operating temperature. Turn A/C off (if equipped). Ensure Malfunction Indicator Light (MIL) is not on.
  2. Disconnect Tan/Black Electronic Spark Timing (EST) by-pass connector wire located near distributor. DO NOT disconnect 4-wire connector at distributor.
  3. Connect timing light to No. 1 spark plug wire. Check timing and adjust if necessary. See V8 IGNITION TIMING  table. Reconnect EST by-pass connector, and clear ECM trouble code.
V8 IGNITION TIMING (DEGREES BTDC @ RPM)

Application Man. Trans. Auto. Trans.
5.0L (VIN H) 0 @ Idle 0 @ Idle
5.7L (VIN K) 0 @ Idle 0 @ Idle
7.4L (VIN N) 4 @ Idle 4 @ Idle