Abstract: An evaporative emissions (EVAP) control system for a vehicle includes a purge pump configured to pump fuel vapor to an engine of the vehicle via a vapor line and a purge valve. The system includes a hydrocarbon (HC) sensor disposed in the vapor line and configured to measure an amount of HC in the fuel vapor pumped by the purge pump to the engine via the vapor line. A controller is configured to: detect an imminent cold start of the engine and, in response to the detecting, perform the cold start of the engine by controlling at least one of the purge pump and the purge valve, based on the measured amount of HC, to deliver a desired amount of fuel vapor to the engine, which decreases HC emissions by the engine.

Abstract: A vapor canister of an evaporative emissions (EVAP) system is configured to store fuel vapor evaporated from a liquid fuel housed in a fuel tank of a vehicle. A boost line is connected between a high-pressure side of a boost system of an engine and the vapor canister, a boost pressure control valve is disposed in-line along the boost line and configured to control an amount of boost pressure provided to the vapor canister, and a set of purge lines are connected between the vapor canister and at least one of the engine, an induction system of the engine, and an exhaust treatment system of the engine. A controller is configured to control the boost pressure control valve to control the boost pressure provided to the vapor canister to control an amount of fuel vapor forced from the vapor canister through at least one of the set of purge lines.

Abstract: A vapor canister of an evaporative emissions (EVAP) system is configured to store fuel vapor evaporated from a liquid fuel housed in a fuel tank of a vehicle. A boost line is connected between a high-pressure side of a boost system of an engine and the vapor canister, a boost pressure control valve is disposed in-line along the boost line and configured to control an amount of boost pressure provided to the vapor canister, and a set of purge lines are connected between the vapor canister and at least one of the engine, an induction system of the engine, and an exhaust treatment system of the engine. A controller is configured to control the boost pressure control valve to control the boost pressure provided to the vapor canister to control an amount of fuel vapor forced from the vapor canister through at least one of the set of purge lines.

Abstract: A diagnostic method and system includes a control valve configured to control an amount of air drawn into an evaporative emissions (EVAP) system through an air filter and a vapor canister, and a pressure sensor configured to measure pressure in the EVAP system. The system also includes a controller configured to detect an engine idle-to-off transition and, in response to detecting the engine idle-to-off transition: receive a first pressure from the pressure sensor, fully open a purge valve connected between the vapor canister and an intake port of an engine, fully close the control valve, monitor one or more second pressures received from the pressure sensor, and detect a malfunction of the EVAP system based on the first pressure, at least one of the one or more second pressures, and a diagnostic threshold.

Abstract: An evaporative emissions (EVAP) control system for a vehicle includes a purge pump configured to pump fuel vapor trapped in a vapor canister to an engine of the vehicle via a vapor line when engine vacuum is less than an appropriate level for delivering fuel vapor to the engine, the fuel vapor resulting from evaporation of a liquid fuel stored in a fuel tank of the engine. The EVAP control system includes a hydrocarbon (HC) sensor disposed in the vapor line and configured to measure an amount of HC in the fuel vapor pumped by the purge pump to the engine via the vapor line. The EVAP control system also includes a controller configured to, based on the measured amount of MC, control at least one of the purge pump and a purge valve to deliver a desired amount of fuel vapor to the engine.

Abstract: An evaporative emissions (EVAP) control system for a vehicle includes a purge pump configured to pump fuel vapor to an engine of the vehicle via a vapor line and a purge valve. The system includes a hydrocarbon (HC) sensor disposed in the vapor line and configured to measure an amount of HC in the fuel vapor pumped by the purge pump to the engine via the vapor line. A controller is configured to: detect an imminent cold start of the engine and, in response to the detecting, perform the cold start of the engine by controlling at least one of the purge pump and the purge valve, based on the measured amount of HC, to deliver a desired amount of fuel vapor to the engine, which decreases HC emissions by the engine.

Abstract: An evaporative emissions (EVAP) control system for a vehicle includes a purge pump configured to pump fuel vapor trapped in a vapor canister to an engine of the vehicle via a vapor line when engine vacuum is less than an appropriate level for delivering fuel vapor to the engine, the fuel vapor resulting from evaporation of a liquid fuel stored in a fuel tank of the engine. The EVAP control system includes a hydrocarbon (HC) sensor disposed in the vapor line and configured to measure an amount of HC in the fuel vapor pumped by the purge pump to the engine via the vapor line. The EVAP control system also includes a controller configured to, based on the measured amount of HC, control at least one of the purge pump and a purge valve to deliver a desired amount of fuel vapor to the engine.

Abstract: A diagnostic method and system includes a control valve configured to control an amount of air drawn into an evaporative emissions (EVAP) system through an air filter and a vapor canister, and a pressure sensor configured to measure pressure in the EVAP system. The system also includes a controller configured to detect an engine idle-to-off transition and, in response to detecting the engine idle-to-off transition: receive a first pressure from the pressure sensor, fully open a purge valve connected between the vapor canister and an intake port of an engine, fully close the control valve, monitor one or more second pressures received from the pressure sensor, and detect a malfunction of the EVAP system based on the first pressure, at least one of the one or more second pressures, and a diagnostic threshold.

Abstract: A method of determining the quality of subsystems of an electronic engine control system is provided. The method monitors an engine parameter representative of a subsystem of interest and compares the parameter to at least one quality limit. The at least one quality limit represents an acceptable performance boundary for a fully functional engine control system. The method then indicates, based on the result of the comparison, whether the subsystem is of satisfactory quality. The method is arranged, without limitation, to determining the quality of start time, start flare, idle control during transmission shift, and speed control.