1989 Mitsubishi Sigma AutomaticFACTORY OEM SERVICE PROCEDURE

Tests W/O Codes: Introduction

Use this section to diagnose driveability problems that exist when a hard fault code is not present or vehicle is not equipped with a self-diagnostic system. Symptom checks are intended to direct the technician to malfunctioning component(s) so that further diagnosis may be performed. A "symptom" should lead to further testing of specific components or systems, or verification of adjustment specifications.

NOTE: For specific component or system tests, see to:

For specifications, refer to:

For adjustment procedures, refer to:

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.