Fuel vapor processing apparatus

A fuel vapor processing apparatus for an engine system including an engine and a fuel tank that stores fuel to be supplied to the engine, the fuel vapor processing apparatus comprising:

• a canister configured to adsorb fuel vapor;
• a vapor passage connecting the canister and the fuel tank, so that fuel vapor produced in the fuel tank is supplied to the canister via the vapor passage;
• a purge passage connecting the canister and the engine, so that fuel vapor desorbed from the canister is purged to the engine via the purge passage;
• a valve disposed in the vapor passage and configured to open and close the vapor passage;
• a pressure detection device coupled to the fuel tank and configured to detect a pressure within the fuel tank;
• and
• a controller coupled to the valve and the pressure detection device, the controller being configured to output a control signal to the valve for opening or closing the valve;
• and
• a determination device configured to determine whether or not the pressure detection device is operating properly to detect the pressure within the fuel tank based on a detection value of the pressure within the fuel tank detected by the pressure detection device at a time after the controller outputs the control signal to the valve to open or close the valve.

A fuel vapor processing apparatus for use with an engine system including an engine and a fuel tank that stores fuel to be supplied to the engine, the fuel vapor processing apparatus comprising:

• a canister configured to adsorb fuel vapor produced in the fuel tank;
• a purge passage connecting the canister and the engine, so that fuel vapor desorbed from the canister is purged to the engine via the purge passage;
• a vapor passage connecting the canister and the fuel tank;
• a valve disposed in the vapor passage and configured to open and close the vapor passage;
• a pressure detection device coupled to the fuel tank and configured to detect a pressure within the fuel tank;
• and
• a controller coupled to the valve and the pressure detection device, the controller being configured to output a control signal to the valve for opening or closing the valve;
• and
• a determination device configured to determine whether or not the valve is operating properly in response to the control signal based on a difference between a first detection value and a second detection value of the pressure detection device;
• wherein:
• the first detection value is detected at a time when or before the controller outputs the control signal to the valve to open or close the valve;
• and
• the second detection value is detected at a predetermined time after the controller outputs the control signal to the valve to open or close the valve.