1990 Jeep WagoneerFACTORY OEM SERVICE PROCEDURE

Hard Starting

Check idle control, EGR valve and control circuits for proper operation. See SYSTEM/COMP TESTS article. Check for A/C ON signal at ECU and for overcharged A/C system. See SYSTEM/COMP TESTS article. Verify injector circuits and fuses for proper operation and check for restricted fuel lines. See BASIC TESTING article.

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.