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Emission Compliance [PYUL]: Outline

WARNING: This page is about a different variant/trim than selected.
EMISSION COMPLIANCE (PYUL) DESCRIPTION AND POSSIBLE CAUSE

Troubleshooting item Emission compliance
Description Fails emissions test.
Possible cause
  • Engine overheating
  • Cooling system malfunction
  • PCM detects DTCs
  • Incorrect fuel injection timing
  • Ignition timing malfunction
    • Spark plug malfunction
    • Ignition coil malfunction
    • CMP sensor malfunction
    • CKP sensor malfunction
  • Purge solenoid valve malfunction
  • Inadequate fuel pressure (high or low pressure side)
    • Fuel leakage at the fuel line and/or fuel injector
    • Fuel pressure sensor or related wiring harness malfunction
    • High pressure fuel pump malfunction
    • Spill valve control solenoid valve control circuit malfunction (damage to driver in PCM caused by short circuit to ground system)
    • Spill valve control solenoid valve malfunction (built-into high pressure fuel pump)
    • Relief valve (built-into high pressure fuel pump) malfunction
    • Fuel line restriction
    • Fuel pump unit malfunction
  • Air leakage from intake-air system
  • Vacuum leakage
  • Intake-air system restriction
  • Charcoal canister (damage, overflow)
  • Improper engine coolant level
  • Excessive carbon built-up in combustion chamber
  • Engine compression pressure malfunction
  • Improper intake valve timing
  • Improper exhaust valve timing
  • Exhaust system and/or TWC restricted
  • Exhaust system leakage
  • TWC malfunction (PCM DTC is stored).
  • Positive crankcase ventilation system malfunction
    • PCV valve malfunction
    • Incorrect PCV valve installation
    • Clogging in positive crankcase ventilation system hoses (PCV valve hose, ventilation hose)
    WARNING:
    • The following troubleshooting flow chart contains the fuel system diagnosis and repair procedures. Read the following warnings before performing the fuel system services: 
      • Fuel vapor is hazardous. It can easily ignite, causing serious injury and damage. Always keep sparks and flames away from fuel. 
      • Highly pressurized fuel may spray out if the fuel line is cut. Due to the following dangers occurring with a fuel spray, always complete the [Fuel Line Safety Procedure] to prevent the fuel from spraying. (Refer to [ BEFORE SERVICE PRECAUTION  ] in Service Information.) 
        • Fuel may cause irritation if it comes in contact with skin and eyes. 
        • If fuel ignites and causes a fire, it may lead to serious injury or death, and damage to property and facilities. 
      • Fuel is highly flammable and dangerous. Fuel line spills and leakage can cause serious injury or death, and damage to equipment. Always Refer to [ QUICK RELEASE CONNECTOR REMOVAL/INSTALLATION (FUEL SYSTEM)  ] before performing the fuel hose installation, and execute the [Fuel Leakage Inspection] after installation. (Refer to [ QUICK RELEASE CONNECTOR (FUEL SYSTEM) REMOVAL/INSTALLATION  ] in Service Information). (Refer to [ AFTER SERVICE PRECAUTION  ] in Service Information.) 
    CAUTION:
    • Disconnecting/connecting the quick release connector without cleaning it may possibly cause damage to the fuel pipe and quick release connector. Always clean the quick release connector joint area before disconnecting/connecting, and make sure that it is free of foreign material. 
System wiring diagram Not applicable