Patent ID: 6189515
Filing Date: 2001-02-20
Classification: F02D

Abstract:
An evaporative emission control system for providing fuel vapor to an automotive engine, said system comprising:a liquid fuel storage tank having an outlet port for allowing fuel vapor to exit the tank;a carbon canister for storing fuel vapor generated within the fuel tank, with the carbon canister having an inlet port for receiving air and an outlet port, said outlet port being adapted for both receiving fuel vapor from said fuel tank and acting as an outlet for stored fuel vapor and air when said carbon canister is purged;a vapor line connecting said tank outlet port to said outlet port of said carbon canister;a purge valve for allowing vapor to flow from said fuel tank and said outlet port of said carbon canister through a purge line and into said engine;a pressure transducer for sensing a purge system pressure within said vapor line; anda controller connected to said purge valve and said pressure transducer, said controller comparing a calculated differential system pressure with a predetermined calibrated differential system pressure and resetting said purge valve based on said compared differential pressures.