Patent ID: 6016690
Filing Date: 2000-01-25
Classification: G01M

Abstract:
A leak detection test method for an evaporative emission space of a fuel storage system of an automotive vehicle comprising:creating a differential between pressure in an evaporative emission space and atmospheric pressure and regulating, by a regulator valve, the created differential to a defined differential sufficient to perform a leak detection test on the evaporative emission space;isolating the evaporative emission space so that reduction in the regulated created differential is indicative of leakage from the evaporative emission space; andsensing reduction in the regulated created differential;in which the step of creating a differential between pressure in an evaporative emission space and atmospheric pressure and regulating, by a regulator valve, the created differential to a defined differential sufficient to perform a leak detection test on the evaporative emission space comprises creating vacuum in the evaporative emission space and regulating the created vacuum to a regulated vacuum by a vacuum regulator valve.