1987 GMC Forward Control 6.2 J, StandardFACTORY OEM SERVICE PROCEDURE

Component Testing: Capacitor

The capacitor is used for radio noise suppression. Set ohmmeter at x1000 scale. Disconnect capacitor. Touch ohmmeter leads to capacitor terminal and ground. Slight needle movement will occur rapidly and return to infinity. A continuous reading other than infinity indicates defective capacitor.

Factory Service Tools

Use the Manual With the Right Hardware

Pair factory procedures with proven DIY tools so the instructions are easier to execute.

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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.