Diagnostic Aids

1999 GMC Forward Control 5.7 R, AutomaticSECTION Diagnostic Aids
WARNING: This page is about a different car, the 2002 Saturn Vue. However, it is still accessible from the selected car via links, so may be relevant.

An external knock sensor circuit fault will not set this DTC. The ECM internally opens each of the wires that connect each knock sensor to the ECM during the P0324 diagnostic.

Replace ECM.

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.