Abstract: An energy module determines an amount of energy consumed by an electric heater of a fuel vapor canister since an ignition system of the vehicle was last transitioned from OFF to ON. A purge valve control module controls opening a purge valve while the ignition system of the vehicle is ON, wherein fuel vapor flows from the vapor canister through the purge valve to an air intake system when the purge valve is open. A heater control module selectively applies power to the electric heater of the fuel vapor canister and, based on at least one of the amount of energy consumed by the electric heater and a mass of fuel vapor that has flowed through the purge valve, selectively disconnects the electric heater from the power until after the ignition system is transitioned from ON to OFF.

Abstract: An energy module determines an amount of energy consumed by an electric heater of a fuel vapor canister since an ignition system of the vehicle was last transitioned from OFF to ON. A purge valve control module controls opening a purge valve while the ignition system of the vehicle is ON, wherein fuel vapor flows from the vapor canister through the purge valve to an air intake system when the purge valve is open. A heater control module selectively applies power to the electric heater of the fuel vapor canister and, based on at least one of the amount of energy consumed by the electric heater and a mass of fuel vapor that has flowed through the purge valve, selectively disconnects the electric heater from the power until after the ignition system is transitioned from ON to OFF.

Abstract: A control system according to the principles of the present disclosure includes a fuel system diagnostic module and a pump control module. The fuel system diagnostic module performs a diagnostic test on a fuel system when a vacuum pump is switched off to prevent flow through the vacuum pump and thereby seal a portion of the fuel system from an atmosphere. The vacuum pump includes a cam ring, a rotor that rotates within the cam ring, and vanes that slide into and out of slots in the rotor as the rotor rotates. The pump control module switches on the vacuum pump for a predetermined period to force the vanes out of the slots and into contact with the cam ring to seal the vacuum pump before switching off the vacuum pump for the fuel system diagnostic test.

Abstract: A system for a vehicle includes a first pressure module and a blockage indication module. The first pressure module receives a signal from a pressure sensor that measures pressure within a fuel vapor purge system. The first pressure module generates a first pressure based on the signal at a first time and generates a second pressure based on the signal at a second time. The second time is after the first time. The blockage indication module indicates whether a blockage is present in the fuel vapor purge system between the pressure sensor and a fuel tank based on a difference between the first and second pressures.

Abstract: A control system includes a switching valve control module, a pressure determination module, and a fuel system diagnostic module. The switching valve control module actuates a switching valve in a fuel system of a vehicle between a first position and a second position, the first position venting a suction side of a vacuum pump in the fuel system to an atmosphere, the second position sealing the suction side of the vacuum pump from the atmosphere. The pressure determination module determines a first pressure on the suction side of the vacuum pump when the switching valve is in the first position, and determines a second pressure on the suction side of the vacuum pump when the switching valve is in the second position. The fuel system diagnostic module selectively diagnoses a fault in the vacuum pump based on the first pressure and the second pressure.

Abstract: A control system according to the principles of the present disclosure includes a fuel system diagnostic module and a pump control module. The fuel system diagnostic module performs a diagnostic test on a fuel system when a vacuum pump is switched off to prevent flow through the vacuum pump and thereby seal a portion of the fuel system from an atmosphere. The vacuum pump includes a cam ring, a rotor that rotates within the cam ring, and vanes that slide into and out of slots in the rotor as the rotor rotates. The pump control module switches on the vacuum pump for a predetermined period to force the vanes out of the slots and into contact with the cam ring to seal the vacuum pump before switching off the vacuum pump for the fuel system diagnostic test.

Abstract: A vehicle includes an engine, a sealed fuel system having a fuel tank, a canister for storing fuel vapor, a vapor circuit external to the fuel tank, and a control valve. The vapor circuit includes an absolute pressure sensor and a switching valve connecting the fuel tank to the control valve. A controller evaluates or diagnoses a vapor purge function of the sealed fuel system using vacuum measurements from the absolute pressure sensor, executing or diagnosing only when the engine is running, purge is enabled, and the pump is off. The controller diagnoses the vapor purge function by comparing the vacuum measurements to a threshold vacuum. An apparatus includes the vapor circuit and controller. A method for diagnosing the vapor purge function includes actuating the switching valve, measuring a vacuum in the system using the absolute pressure sensor, and comparing the measured vacuum to a threshold vacuum.

Abstract: A fuel system diagnostic wakeup system for a vehicle includes a first control module. The first control module generates a wakeup request, powers off when the vehicle powers off, and powers on and performs a fuel system diagnostic in response to a wakeup signal while the vehicle is powered off. A second control module independent of the first control module receives the wakeup request and generates the wakeup signal after the vehicle powers off based on the wakeup request.

Abstract: A system for a vehicle includes a first pressure module and a blockage indication module. The first pressure module receives a signal from a pressure sensor that measures pressure within a fuel vapor purge system. The first pressure module generates a first pressure based on the signal at a first time and generates a second pressure based on the signal at a second time. The second time is after the first time. The blockage indication module indicates whether a blockage is present in the fuel vapor purge system between the pressure sensor and a fuel tank based on a difference between the first and second pressures.

Abstract: A vehicle includes a sealed fuel system and a controller. The fuel system includes a fuel tank, a fuel cap, a control orifice, and an absolute pressure sensor. The controller associates a threshold large leak in the fuel system with a fuel cap sealing error. The controller detects completion of a prior refueling event, compares measurements from the pressure sensor to a reference vacuum across the control orifice to determine the presence of the threshold large leak, and sets a diagnostic code corresponding to the large leak only upon completion of the prior refueling event. A method for detecting the large leak includes detecting completion of the refueling event, comparing vacuum measurements from the absolute pressure sensor to a reference vacuum across the orifice to determine the presence of the large leak, and setting a diagnostic code corresponding to the large leak only upon completion of the prior refueling event.

Abstract: A control module and method for operating the same includes a diurnal control valve module that opens a diurnal control valve (DCV) and an evaporative leak check module (ELCM) diverter valve control module that switches on an ELCM diverter valve. The control module includes a correlation module performs a correlation of a ELCM pressure signal and a fuel tank pressure signal and that generates a fault signal in response to the correlation when the DCV valve is open and the ELCM diverter valve is on.

Abstract: A control system comprising a wind condition determination module that determines a wind condition and a leak detection test control module that selectively diagnoses a vapor leak associated with a vehicle based on the wind condition. A method comprising determining a wind condition and selectively diagnosing a vapor leak associated with a vehicle based on the wind condition.

Abstract: A control system includes a switching valve control module, a pressure determination module, and a fuel system diagnostic module. The switching valve control module actuates a switching valve in a fuel system of a vehicle between a first position and a second position, the first position venting a suction side of a vacuum pump in the fuel system to an atmosphere, the second position sealing the suction side of the vacuum pump from the atmosphere. The pressure determination module determines a first pressure on the suction side of the vacuum pump when the switching valve is in the first position, and determines a second pressure on the suction side of the vacuum pump when the switching valve is in the second position. The fuel system diagnostic module selectively diagnoses a fault in the vacuum pump based on the first pressure and the second pressure.

Abstract: A vehicle includes a sealed fuel system and a controller. The fuel system includes a fuel tank, a fuel cap, a control orifice, and an absolute pressure sensor. The controller associates a threshold large leak in the fuel system with a fuel cap sealing error. The controller detects completion of a prior refueling event, compares measurements from the pressure sensor to a reference vacuum across the control orifice to determine the presence of the threshold large leak, and sets a diagnostic code corresponding to the large leak only upon completion of the prior refueling event. A method for detecting the large leak includes detecting completion of the refueling event, comparing vacuum measurements from the absolute pressure sensor to a reference vacuum across the orifice to determine the presence of the large leak, and setting a diagnostic code corresponding to the large leak only upon completion of the prior refueling event.

Abstract: A fuel system diagnostic wakeup system for a vehicle includes a first control module. The first control module generates a wakeup request, powers off when the vehicle powers off, and powers on and performs a fuel system diagnostic in response to a wakeup signal while the vehicle is powered off. A second control module independent of the first control module receives the wakeup request and generates the wakeup signal after the vehicle powers off based on the wakeup request.

Abstract: A vehicle includes an engine, a sealed fuel system having a fuel tank, a canister for storing fuel vapor, a vapor circuit external to the fuel tank, and a control valve. The vapor circuit includes an absolute pressure sensor and a switching valve connecting the fuel tank to the control valve. A controller evaluates or diagnoses a vapor purge function of the sealed fuel system using vacuum measurements from the absolute pressure sensor, executing or diagnosing only when the engine is running, purge is enabled, and the pump is off. The controller diagnoses the vapor purge function by comparing the vacuum measurements to a threshold vacuum. An apparatus includes the vapor circuit and controller. A method for diagnosing the vapor purge function includes actuating the switching valve, measuring a vacuum in the system using the absolute pressure sensor, and comparing the measured vacuum to a threshold vacuum.

Abstract: A control system comprising a detection module that detects at least one of a vehicle speed and an engine speed and a canister vent valve control module that selectively modulates the canister vent valve based on at least one of the vehicle speed and the engine speed. A method comprising detecting at least one of a vehicle speed and an engine speed and selectively modulating a canister vent valve based on at least one of the vehicle speed and the engine speed.

Abstract: A control module and method for operating the same includes a diurnal control valve module that opens a diurnal control valve (DCV) and an evaporative leak check module (ELCM) diverter valve control module that switches on an ELCM diverter valve. The control module includes a correlation module performs a correlation of a ELCM pressure signal and a fuel tank pressure signal and that generates a fault signal in response to the correlation when the DCV valve is open and the ELCM diverter valve is on.

Abstract: A control system comprising a detection module that detects at least one of a vehicle speed and an engine speed and a canister vent valve control module that selectively modulates the canister vent valve based on at least one of the vehicle speed and the engine speed. A method comprising detecting at least one of a vehicle speed and an engine speed and selectively modulating a canister vent valve based on at least one of the vehicle speed and the engine speed.

Abstract: A control system comprising a wind condition determination module that determines a wind condition and a leak detection test control module that selectively diagnoses a vapor leak associated with a vehicle based on the wind condition. A method comprising determining a wind condition and selectively diagnosing a vapor leak associated with a vehicle based on the wind condition.