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EVAP Leak Monitor Large Leak Detected

CODE NUMBER
Scan tool A1 (161)
General scan tool P0455
MIL 31

CODE NAME
EVAP Leak Monitor Large Leak Detected

BACKGROUND
- The PCM monitors that the fuel tank, purge lines, etc. are sealed well.
- When monitoring, the PCM pressurizes the purge lines by activating the leak detection pump with the canister ventilation valve (incorporated in the solenoid) closed.
- It the fuel tank and purge lines are sealed correctly, the pressure will rise well by activating the solenoid specific times.
- After the pressure rises well, the diaphragm inside the solenoid will not work any more.
- If the purge air leaks excessively, the solenoid should be activated much more than specific times.

CHECK AREA
- All areas of evaporative system.

JUDGEMENT CRITERIA
- When a hole 1 - 2 mm in diameter is opened in the evaporative system When a considerable amount of evaporating gas leak is detected.

PROBABLE CAUSE
- Defective leak detection pump
- Defective fuel tank filler tube assembly
- Defective fuel tank
- Defective evaporative emission canister
- Defective hose between leak detection pump and intake manifold
- Defective hose between liquid separator and evaporative emission canister
- Defective hose between liquid separator and fuel cut-off valve
- Defective hose between evaporative emission purge solenoid valve and evaporative emission canister
- Defective hose between leak detection pump and evaporative emission canister








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