P0455 EVAP Leak Monitor Large Leak Detected
NAME OF CODEEvap System Large Leak
WHEN MONITORED
See DRB III
SET CONDITION
See DRB III
THEORY OF OPERATION
The first portion of the test determines whether or not a line is pinched in the system. If the pump rate falls to zero too rapidly, the PCM determines that there is not enough space to pressurize, this indicates a possible pinched line. If there is a leak present in the EVAP system, the cycle rate falls to a rate proportional to the size of the leak. By monitoring the cycle rate of the pump, the PCM is able to calculate the size of the leak.
POSSIBLE CAUSE
- A leak in the evaporative system larger than 0.080"
- Leak detection pump failure