Hyundai GENESIS COUPE BK 2010 Manual page 260

Evaporative System Monitoring
Evaporative Emission Control Monitoring System consists of fuel vapor generation, evacuation, and leakage check step.
At first, the OBD-II system checks if vapor generation due to fuel temperature is small enough to start monitoring. Then
it evacuates the evaporative system by means of PCSV with ramp in order to maintain a certain vacuum level. The
final step is to check if there is vacuum loss by any leakage of the system.
Vapor Generation Checking
During stabilization period, the PCSV and the CCV are closed. The system pressure is measured as starting pressure
(DP_A). After a certain defined period (T1), the system pressure (DP_B) is measured again and the difference from the
starting pressure is calculated. If this difference (DP_B - DP_A) is bigger than a threshold, there should be excessive
vapor and the monitor is aborted for next checking. On the contrary, if the difference is lower than another negative
threshold, PCSV is regarded as malfunction such as clogged at open position.
Evacuation
PCSV is opened with a certain ramp for the pressure to reach down to a certain level. If pressure can't be lowered
below a threshold, the system is regarded as fuel cap-opened or having a large leakage.
Leaking Checking
PCSV is closed and the system waits for a period to get stabilized pressure. During checking period (T2), the system
measures the beginning and the end of the system pressure (DP_C, DP_D). The diagnosis value is the pressure
difference corrected by natural vapor generation (DP_B - DP_A) rate from the vapor generation checking step.
Evaporative System Monitoring
Evaporative And ORVR Emission Control System
This system consists of a fill vent valve, fuel shut-off valve, fuel cut valve (for roll over), two way valve