The present disclosure describes methods and systems for determining a flow of a combustible portion of vent gas delivered to an engine. The flow rate measurement may be performed by using the engine response to a relatively short (e.g. 1 to 5 s) reduction of the vent gas flow. A cross-correlation between RPM data of the engine and a reference signal corresponding to a state of a valve configured to reduce the vent gas flow is determined, and a flow rate of the combustible portion of the vent gas delivered to the engine is determined from the maximum value of the cross-correlation.

A heating system includes at least one electric heater disposed within the fluid flow system. A control device includes a microprocessor and is configured to determine a temperature of the at least one electric heater based on a model and at least one input from the fluid flow system. The control device is configured to provide power to the at least one electric heater based on the temperature of the at least one electric heater.

A heating system includes at least one electric heater disposed within the fluid flow system. A control device includes a microprocessor and is configured to determine a temperature of the at least one electric heater based on a model and at least one input from the fluid flow system. The control device is configured to provide power to the at least one electric heater based on the temperature of the at least one electric heater.

The present invention provides a testing device testing a multi-cylinder engine including a plurality of ports including an intake port and an exhaust port in a pseudo driving state. The device includes a plurality of pressure inspection units and at least one opening/closing mechanism. Each of the plurality of pressure inspection units includes a pipeline connected to one of the plurality of ports, a sensor for detecting a pressure in the pipeline and a valve for opening/closing the pipeline. The opening/closing mechanism includes one actuator and a transmission mechanism connected to the actuator and transmitting a driving force of the actuator to an operation unit of each of the plurality of valves to open and close the plurality of valves.

The present invention provides a testing device testing a multi-cylinder engine including a plurality of ports including an intake port and an exhaust port in a pseudo driving state. The device includes a plurality of pressure inspection units and at least one opening/closing mechanism. Each of the plurality of pressure inspection units includes a pipeline connected to one of the plurality of ports, a sensor for detecting a pressure in the pipeline and a valve for opening/closing the pipeline. The opening/closing mechanism includes one actuator and a transmission mechanism connected to the actuator and transmitting a driving force of the actuator to an operation unit of each of the plurality of valves to open and close the plurality of valves.

Examples of the present disclosure describe systems and methods for determining a state of an air diverter valve of an air induction system of a vehicle. The determined state of the air diverter valve may be based on an intercooler-based estimated ambient air temperature and a comparison between an ambient air temperature sensor value and a pre-compressor sensor value.

A method for localizing restrictions in a fuel system during refueling, comprising: monitoring fuel tank pressure, fuel vapor canister temperature, and evaporative leak check module pressure during a refueling event; and responsive to a premature shutoff event, indicating a location of a restriction among a plurality of locations based on whether monitored pressure and temperature changes during the refueling event are greater than respective thresholds. In this way, the cause of a premature shutoff event may be diagnosed without requiring additional sensors within the fuel system.

A method for localizing restrictions in a fuel system during refueling, comprising: monitoring fuel tank pressure, fuel vapor canister temperature, and evaporative leak check module pressure during a refueling event; and responsive to a premature shutoff event, indicating a location of a restriction among a plurality of locations based on whether monitored pressure and temperature changes during the refueling event are greater than respective thresholds. In this way, the cause of a premature shutoff event may be diagnosed without requiring additional sensors within the fuel system.

A variety of methods and arrangements for detecting failure of the commanded air induction in an internal combustion engine are described. In some embodiments, the intake manifold pressure is monitored. An air induction event generates a fluctuation in the intake manifold pressure, which is recorded. The signal is processed through a diagnostic filter to help determine whether the actual induction matched the commanded induction. In other embodiments, measured crankshaft acceleration is compared with estimated crankshaft acceleration. If the two quantities differ by a threshold amount an induction fault is detected. The two detection methods may also be combined. The describe approaches are particularly well suited for use in engines operating in a skip fire mode with cylinder deactivation and/or a dynamic firing level modulation mode.

A variety of methods and arrangements for detecting failure of the commanded air induction in an internal combustion engine are described. In some embodiments, the intake manifold pressure is monitored. An air induction event generates a fluctuation in the intake manifold pressure, which is recorded. The signal is processed through a diagnostic filter to help determine whether the actual induction matched the commanded induction. In other embodiments, measured crankshaft acceleration is compared with estimated crankshaft acceleration. If the two quantities differ by a threshold amount an induction fault is detected. The two detection methods may also be combined. The describe approaches are particularly well suited for use in engines operating in a skip fire mode with cylinder deactivation and/or a dynamic firing level modulation mode.