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.
2002 Mitsubishi Lancer LSFACTORY OEM SERVICE PROCEDURE
Engine Controls - Self-Diagnostics
- Introduction
- Self-Diagnostic System
- Verifying Repairs
- Summary
- Intermittent Diagnostic Trouble Codes
- Diagnostic Circuit Check
- Component Locations
- Diagnostic Trouble Code Definitions
- Diagnostic Tests
- DTC P0101: Volume Airflow Circuit Range/Performance Problem
- DTC P0102: Volume Airflow Circuit Low Input
- DTC P0106: Barometric Pressure Circuit Range/Performance Problem
- DTC P0107: Barometric Pressure Circuit Low Input
- DTC P0108: Barometric Pressure Circuit High Input
- DTC P0111: Intake Air Temperature Circuit Malfunction
- DTC P0112: Intake Air Temperature Circuit Low Input
- DTC P0113: Intake Air Temperature Circuit High Input
- DTC P0116: Engine Coolant Temperature Circuit Range/Performance Problem
- DTC P0117: Engine Coolant Temperature Circuit Low Input
- DTC P0118: Engine Coolant Temperature Circuit High Input
- DTC P0121: Throttle Position Sensor Circuit Range/Performance Problem
- DTC P0122: Throttle Position Sensor Circuit Low Input
- DTC P0123: Throttle Position Sensor Circuit High Input
- DTC P0125: Insufficient Coolant Temperature For Closed Loop Fuel Control
- DTC P0128: Coolant Thermostat Malfunction
- DTC P0132: Heated Oxygen Sensor Circuit High Voltage (Sensor 1)
- DTC P0133: Heated Oxygen Sensor Circuit Slow Response (Sensor 1)
- DTC P0134: Heated Oxygen Sensor Circuit No Activity Detected (Sensor 1)
- DTC P0135: Heated Oxygen Sensor Heater Circuit (Sensor 1)
- DTC P0137: Heated Oxygen Sensor Circuit Low Voltage (Sensor 2)
- DTC P0138: Heated Oxygen Sensor Circuit High Voltage (Sensor 2)
- DTC P0139: Heated Oxygen Sensor Circuit Slow Response (Sensor 2)
- DTC P0141: Heated Oxygen Sensor Heater Circuit (Sensor 2)
- DTC P0171: System Too Lean
- DTC P0172: System Too Rich
- DTC P0181: Fuel Temperature Sensor Circuit Range/Performance Problem
- DTC P0182: Fuel Temperature Sensor Circuit Low Input
- DTC P0183: Fuel Temperature Sensor Circuit High Input
- DTC P0201, DTC P0202, DTC P0203 Or DTC P0204
- DTC P0300: Random/Multiple Cylinder Misfire Detected
- DTC P0301, DTC P0302, DTC P0303 Or DTC P0304
- DTC P0325: Knock Sensor Circuit
- DTC P0335: Crankshaft Position Sensor Circuit
- DTC P0340: Camshaft Position Sensor Circuit
- DTC P0401: EGR Flow Insufficient Detected
- DTC P0403: EGR Control Circuit
- DTC P0421: Warm Up Catalyst Efficiency Below Threshold
- DTC P0441: Evaporative Emission Control System Incorrect Purge Flow
- DTC P0442: Evaporative Emission Control System Leak Detected (Small Leak)
- DTC P0443: Evaporative Emission Control System Purge Control Valve Circuit
- DTC P0446: Evaporative Emission Control System Vent Control Circuit
- DTC P0451: Evaporative Emission Control System Pressure Sensor Range/Performance
- DTC P0452: Evaporative Emission Control System Pressure Sensor Low Input
- DTC P0453: Evaporative Emission Control System Pressure Sensor High Input
- DTC P0455: Evaporative Emission Control System Leak Detected (Gross Leak)
- DTC P0456: Evaporative Emission Control System Leak Detected (Very Small Leak)
- DTC P0461: Fuel Level Sensor Circuit Range/Performance Fuel Gauge Unit Circuit
- DTC P0500: Vehicle Speed Sensor Circuit (M/T)
- DTC P0506: Idle Control System Rpm Lower Than Expected
- DTC P0507: Idle Control System Rpm Higher Than Expected
- DTC P0551: Power Steering Pressure Sensor Circuit Range/Performance
- DTC P1400: Manifold Differential Pressure Sensor Circuit Malfunction
- DTC P1500: Generator Fr Terminal Circuit Malfunction
- DTC P1603: Battery Backup Circuit Malfunction
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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