Diagnostic Aids

1997 Chevrolet Chevy Express G3500, Van Cargo, 6.5 FSECTION Diagnostic Aids
WARNING: This page is about a different car, the 1995 Pontiac Trans Sport and 1995 Chevrolet Lumina APV. However, it is still accessible from the selected car via links, so may be relevant.

Code 43 can be caused by a faulty knock sensor connection at ESC module or engine control module. Also, check controller-to-control module signal line for an open or short to ground.

Fig 1: Code 43 Schematic (3.1L FWD Van) Knock Sensor With Spark Control Module
G94G66031
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.