Patent ID: 6213102
Filing Date: 2001-04-10
Classification: F02M

Abstract:
An evaporated fuel treatment system for an internal combustion engine comprising:a fuel tank;a canister having an interior and an opening that opens the interior to the atmosphere, and which adsorbs evaporated fuel generated inside the fuel tank;a charging passage that communicates with said fuel tank and with said canister;a pressure adjustment valve provided in said charging passage;an internal pressure sensor provided upstream from said pressure adjustment valve to detect and output the vapor pressure inside said fuel tank; anda controller configured to detect leakage on the upstream side of said pressure adjustment valve according to the output of said sensor, said controller having at least a first stored reference value for a first leak diameter to be detected and a second stored reference value for a second leak diameter to be detected, and configured to determine the absence of leakage by comparing the output of said internal pressure sensor with said first and second reference values.