IDI (2.3L): Spark

1991 Pontiac Firebird Formula, 5.0 F, Standard, M39SECTION Spark
WARNING: This page does not describe the selected car, but rather 39 other vehicles, including the 1992 Saturn SL2, 1992 Saturn SL1, 1992 Saturn SL, 1992 Saturn SC, and 1992 Pontiac Sunbird. However, it is still accessible from the selected car via links, so may be relevant.

Disconnect tachometer wire from IDI module (if equipped). A shorted tachometer will not allow vehicle to start. Temporarily remove IDI assembly and install spark plug Jumper Wires (J36012). Check for adequate spark with Spark Tester (ST-125). Check for spark on 2 adjacent plug wires (1-2 or 3-4, not 2-3). Leave matching plug wire connected while checking for spark. When removing spark plug wire from spark plug, twist and pull on boot. DO NOT pull on wire.

RENDER: 1.0x

NO RELATED

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • β€’ You smell fuel, burning insulation, or see smoke.
  • β€’ Brakes feel soft, pull hard to one side, or make grinding noises.
  • β€’ The engine overheats, stalls repeatedly, or misfires under load.
  • β€’ You are missing required tools, torque specs, or safe lifting equipment.
  • β€’ You are not confident in the next step or safety outcome.