Diagnostic Aids

1988 Chevrolet Chevy Van G30, 6.2 J, 400/M40SECTION Diagnostic Aids

"SCAN" tester does not have any ability to help diagnose ignition system.

See INTERMITTENT TROUBLE CODES in the CCC TESTS W/O CODES article in this section.

Fig 1: Ignition System Check Flow Chart (Remote Coil/Sealed Connector Distributor) (Except 2.5L "S/T" Series)
G120845
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.