초록 ▼

A apparatus and method of detecting a leak in an evaporative emissions system measures vapor flow out of the evaporative emissions system while maintaining a zero pressure difference from inside a fuel tank to atmosphere and provides a reference vapor flow variable dependent on the measurement (317)

A apparatus and method of detecting a leak in an evaporative emissions system measures vapor flow out of the evaporative emissions system while maintaining a zero pressure difference from inside a fuel tank to atmosphere and provides a reference vapor flow variable dependent on the measurement (317). A pressurized vapor and leak flow variable is measured (323) dependent on measured vapor flow out of the evaporative emissions system while maintaining a pressure difference of 10″of water from inside the fuel tank to atmosphere. A leak is indicated (327) if a difference between the reference vapor flow variable and the pressurized vapor and leak flow variable is greater than a predetermined leak flow factor.

대표청구항 ▼

A method of detecting a leak in an evaporative emissions system for a vehicle, the method comprising the steps of: measuring vapor flow out of the evaporative emissions system while maintaining a substantially zero pressure difference from inside a fuel tank to atmosphere and providing a reference v

A method of detecting a leak in an evaporative emissions system for a vehicle, the method comprising the steps of: measuring vapor flow out of the evaporative emissions system while maintaining a substantially zero pressure difference from inside a fuel tank to atmosphere and providing a reference vapor flow variable dependent on the measurement; measuring vapor flow out of the evaporative emissions system while maintaining another pressure difference from inside the fuel tank to atmosphere and providing a pressurized vapor and leak flow variable dependent on the measurement; indicating a leak if a difference between the reference vapor flow variable and the pressurized vapor and leak flow variable is greater than a predetermined leak flow factor.