Patent ID: 6105556
Filing Date: 2000-08-22
Classification: F02M

Abstract:
An evaporative system for precisely detecting a pressure therein to determine leakage accurately, comprising:a fuel tank;an evaporative gas line connected to said fuel tank;a canister for receiving evaporated gas produced in a fuel tank through said evaporative gas line, said canister containing an adsorbent for temporarily adsorbing the evaporated gas;a purge line operatively connected with the canister and having a purge valve for discharging said adsorbed evaporated gas to an intake tube of an engine;a gauge line branching off from one of said purge line and said evaporated gas line connecting said fuel tank to said canister, said gauge line communicating with one of said intake tube and the ambient atmosphere; anda control device operatively associated with the canister, the purge line and the gauge line and configured to selectively open and close the purge line and gauge line caused by fuel evaporation by using a calculated pressure change which is representative of the pressure chance caused by the evaporated gas and thereby eliminate effects of increased pressures within said fuel tank on the accuracy of leakage determination.