Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
1990 Mitsubishi Montero Base, AutomaticFACTORY OEM SERVICE PROCEDURE
Engine Controls - Self-Diagnostics
- Introduction
- Self-Diagnostic System
- Diagnostic Trouble Code Definitions
- Diagnostic Tests
- Components Inspection Procedure Using Multi-Use Tester
- Power Supply & Ignition Switch-IG
- Engine Control Unit Power Ground
- Fuel Pump
- Airflow Sensor
- Intake Air Temperature Sensor
- Barometric Pressure Sensor
- Engine Coolant Temperature Sensor
- Throttle Position Sensor
- Idle Position Switch
- Top Dead Center Sensor
- Crank Angle Sensor
- Ignition Switch-St (M/T)
- Ignition Switch-St & Inhibitor Switch (A/T)
- Vehicle Speed Sensor
- Power Steering Oil Pressure Switch (A/T)
- Air Conditioner Switch & Power Relay
- Oxygen Sensor
- Injectors
- Idle Speed Control Servo (Stepper Motor)
- Ignition Coil & Power Transistor
- Purge Control Solenoid Valve
- Wiring Diagrams
Factory Service Tools
Use the Manual With the Right Hardware
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.
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