Emission Control System (For Sedan) -- On-Vehicle Inspection |
1. INSPECT FUEL CUT-OFF RPM |
Start and warm up the engine.
Increase the engine speed to approximately 3,500 rpm.
Using a sound scope, check the operation sound of the injector.
Release the accelerator pedal. Check that the operation noise stops momentarily and then resumes.
2. VISUALLY INSPECT HOSES, CONNECTIONS AND GASKETS |
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Check that there are no cracks, leakage or scratches on the hoses, connections or gaskets.
- HINT:
- Removing the oil level gauge, oil filter cap or PCV hose may cause the engine to malfunction or stall.
- Disconnections, looseness or cracks in the parts of the air induction system between the intake system and cylinder head will allow air suction and cause the engine to run improperly.
3. CHECK LINE AND CONNECTORS |
Visually check for loose connections, sharp bends and damage.
4. CHECK FUEL TANK ASSEMBLY |
Visually check for deformation, cracks and fuel leakage.
5. CHECK FUEL TANK AND VENT LINE |

Disconnect the vent line hose from the canister.
Connect the pressure gauge to the vent line hose.
Apply 4 kPa (41 kgf/cm2, 30 mmHg) of pressure to the vent line of the fuel tank.
- HINT:
- Perform this inspection with the fuel tank less than 90% full. When the fuel tank is full, the fuel cutoff valve closes and the pressure is released through the 2 mm orifice. As a result, when the fuel tank cap is removed, the pressure does not decrease smoothly.
Check that the fuel tank pressure is maintained for some time, and does not decrease immediately.
- HINT:
- If the pressure decreases immediately, one of the following may apply:
- The fuel tank cap is not completely tightened.
- The fuel tank cap is damaged.
- Air is leaking from the vent line.
- The fuel tank is damaged.
When the fuel tank cap is removed, check that the pressure is released smoothly.
- HINT:
- If the pressure does not drop, replace the fuel tank assembly.
Reconnect the vent line hose to the canister.
6. CHECK AIR INLET LINE |
Disconnect the air inlet line hose from the canister.
Check that air flows freely into the air inlet line.
- HINT:
- If air does not flow freely into the air inlet line, repair or replace it.
Reconnect the air inlet line hose to the canister.