Abstract: A valve assembly for an air flow system, where the air flow system has a turbocharger unit and a venturi valve member for receiving a portion of the pressurized air from the turbocharger unit, and generating back pressure. The valve assembly includes a bypass switching valve and a bypass check valve. During a first mode of operation, the valve assembly is exposed to vacuum pressure, and the bypass check valve is exposed to the vacuum pressure such that the bypass check valve is placed in a closed position. During a second mode of operation the turbocharger unit is activated, pressurized air flows through the bypass switching valve, and places the bypass check valve in an open position, and the back pressure generated by the venturi valve member and the pressurized air from the turbocharger unit creates a pressure differential in the bypass check valve.

Abstract: A system which includes a turbo bypass switching valve (BSV) positioned at a beneficial location as a direct mount on an air box to achieve compliance to OBD hose-off requirement via electronic actuation of the BSV and monitoring of the fuel tank pressure sensor for pressure change. When the turbocharger unit is generating pressurized air, the turbo BSV is open, and vapor is passing through the purge valve, some level of vacuum in the fuel tank is sensed. By closing the BSV, flow through the venturi is reduced, producing both less vacuum and a change in fuel tank pressure. The pressure change does not occur if any of the hoses become disconnected. This results in a simple OBD “venture hose off” check without additional components.

Abstract: A system which includes a turbo bypass switching valve (BSV) positioned at a beneficial location as a direct mount on an air box to achieve compliance to OBD hose-off requirement via electronic actuation of the BSV and monitoring of the fuel tank pressure sensor for pressure change. When the turbocharger unit is generating pressurized air, the turbo BSV is open, and vapor is passing through the purge valve, some level of vacuum in the fuel tank is sensed. By closing the BSV, flow through the venturi is reduced, producing both less vacuum and a change in fuel tank pressure. The pressure change does not occur if any of the hoses become disconnected. This results in a simple OBD “venture hose off” check without additional components.

Abstract: A valve assembly for an air flow system, where the air flow system has a turbocharger unit and a venturi valve member for receiving a portion of the pressurized air from the turbocharger unit, and generating back pressure. The valve assembly includes a bypass switching valve and a bypass check valve. During a first mode of operation, the valve assembly is exposed to vacuum pressure, and the bypass check valve is exposed to the vacuum pressure such that the bypass check valve is placed in a closed position. During a second mode of operation the turbocharger unit is activated, pressurized air flows through the bypass switching valve, and places the bypass check valve in an open position, and the back pressure generated by the venturi valve member and the pressurized air from the turbocharger unit creates a pressure differential in the bypass check valve.