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Ignition Timing

  1. Set parking brake. Block drive wheels. Place transmission in Neutral or Park. Warm engine to 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, or in cab under glove box. 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 IGNITION TIMING . Reconnect EST by-pass connector. Clear DTC.
IGNITION TIMING (DEGREES BTDC @ RPM)

Application Man. Trans. Auto. Trans.
7.4L (VIN N) 4 @ Idle 4 @ Idle
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