Section 28 (Engine Controls - Basic Testing - 6.5L Diesel): Summary

1987 Chevrolet Chevy Van G30, 5.7 K, 400/M40SECTION Summary
WARNING: This page does not describe the selected car, but rather 20 other vehicles, including the 1994 GMC Yukon, 1994 GMC Vandura Special, 1994 GMC Vandura, 1994 GMC Suburban, and 1994 GMC Rally Camper Special. However, it is still accessible from the selected car via links, so may be relevant.

If faults were not found while performing BASIC DIAGNOSTIC PROCEDURES, proceed to appropriate G - 6.5L TESTS W/ CODES article in the ENGINE PERFORMANCE section below. If no hard codes are found in self-diagnostics, or vehicle does not have a self-diagnostic system, proceed to TESTS W/O CODES - 6.5L DIESEL article in the ENGINE PERFORMANCE section for diagnosis by symptom (i.e., ROUGH IDLE, NO START, etc.) or intermittent diagnostic procedures.

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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.