Methods and systems for diagnosing operational status of a carbon filled canister heater are described. The methods and systems may include activating an evaporative emissions system heater, a pump, and a canister purge valve to determine if long chain hydrocarbons are released from a carbon filled canister. Release of long chain hydrocarbons from the carbon filled canister may be indicative of desired operation of a carbon filled canister heater.

Methods and systems are provided for reverse purging of a fuel vapor canister of an engine. In one example, a method may include heating a fuel vapor canister, sealing a fuel tank in order to generate a vacuum in the fuel tank, and in response to the pressure in the fuel tank reaching a target vacuum, initiating reverse purging of the fuel vapor canister.

Methods and systems are provided for diagnosing a heating element coupled to a canister of an evaporative emissions control (EVAP) system. In one example, a method (or system) may include evacuating the canister at different temperature conditions, and diagnosing the heating element based on the different times taken to evacuate the canister at the different temperature conditions.

A method of controlling an evaporative emissions system for a vehicle is provided. A fuel system for a vehicle and a vehicle are also provided. A signal indicative of an entry condition associated with a secondary air flow path for a purge of an evaporative emissions canister is received. A filter is decoupled from a port of the evaporative emissions canister in response to receiving the signal and prior to the evaporative emissions canister purge. The evaporative emissions canister is purged by flowing atmospheric air into the port and through the evaporative emissions canister while the filter is decoupled from the port. The filter is coupled to the port of the evaporative emissions canister after purging the canister.

A vehicle includes a fuel tank, a canister, a first valve, a second valve, a heater, and a controller. The fuel tank is configured to store fuel. The canister is in fluid communication with the fuel tank and is configured to receive and store evaporated fuel from the fuel tank. The first valve is disposed between the fuel tank and the canister. The second valve is disposed between the canister and ambient surroundings. The heater is disposed within the canister. The controller is programmed to, periodically initiate diagnostic tests that are configured to determine if the heater is operating properly, if the heater is unable to turn off, or if the heater is unable to turn on.

Methods and systems for deicing an engine air intake filter and an engine throttle are described. The methods and systems may include activating an evaporative emissions system heater and a pump to de-ice the engine air intake filter and the engine throttle. The deicing may be performed when an engine of a vehicle is not operating.

Methods and systems are provided for reverse purging of a fuel vapor canister of an engine. In one example, a method may include heating a fuel vapor canister, sealing a fuel tank in order to generate a vacuum in the fuel tank, and in response to the pressure in the fuel tank reaching a target vacuum, initiating reverse purging of the fuel vapor canister.

Provided is a canister that includes a first adsorbing layer K1 including a first adsorbing material Q1 as an adsorbing material Q and a second adsorbing layer K2 including, as the adsorbing material Q, a second adsorbing material Q2 different from the first adsorbing material Q1. The first absorbing layer K1 and the second absorbing layer K2 are provided inside a casing 10. In a flowing direction of fuel vapor J between one end and another end of the casing 10, the first adsorbing layer K1 is disposed at a position in contact with an air port 10a at the other end, and the second adsorbing layer K2 is disposed closer to the one end than the first adsorbing layer K1 is. The first adsorbing material Q1 adsorbs the fuel vapor J at an adsorbing rate that is lower than an adsorbing rate of the second adsorbing material Q2.

Provided is a canister that includes a first adsorbing layer K1 including a first adsorbing material Q1 as an adsorbing material Q and a second adsorbing layer K2 including, as the adsorbing material Q, a second adsorbing material Q2 different from the first adsorbing material Q1. The first absorbing layer K1 and the second absorbing layer K2 are provided inside a casing 10. In a flowing direction X of fuel vapor J between one end and another end of the casing 10, the first adsorbing layer K1 is disposed at a position in contact with an air port 10a at the other end, and the second adsorbing layer K2 is disposed closer to the one end than the first adsorbing layer K1 is. The first adsorbing material Q1 adsorbs the fuel vapor J at an adsorbing rate that is higher than an adsorbing rate of the second adsorbing material Q2.

Methods and systems are provided for an ultrasonic wave generator within a vehicle emissions control system. In one example, a frequency of ultrasonic waves may be applied to a fuel vapor canister, the frequency adjusted in response to an estimate of hydrocarbon distribution within a vapor canister received from temperature and hydrocarbon sensor outputs.