Diagnostic Aids

1985 Chevrolet Chevy Van G20, 6.2 C, StandardSECTION Diagnostic Aids
WARNING: This page does not describe the selected car, but rather 6 other vehicles, including the 1994 GMC Vandura, 1994 GMC Rally, 1994 GMC Pickup, 1994 Chevrolet Sportvan, and 1994 Chevrolet Pickup. However, it is still accessible from the selected car via links, so may be relevant.

The scan tester cannot help diagnose a Code 42 problem. See INTERMITTENTS in appropriate TESTS W/O CODES article in this section. See below.

  • H - TESTS W/O CODES - GASOLINE (for "C" & "K" Series)
  • H - TESTS W/O CODES - GASOLINE (For "G" & "P" Series)
Fig 1: Code 42 Schematic ("C" & "K" Series Exc. 5.0L M/T) Ignition Control
G93I76420
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.