Patent ID: 6736117
Filing Date: 2004-05-18
Classification: F02M

Abstract:
An abnormality detecting device for an evaporative fuel processing system including:a fuel tank; a canister for trapping evaporative fuel generated in said fuel tank; a charging passage for connecting said fuel tank and said canister; an on-off valve provided in said charging passage for opening and closing said charging passage; and a pressure sensor provided in said charging passage at a position between said on-off valve and said fuel tank, said abnormality detecting device comprising: pressure reducing means for reducing a pressure in said canister to a pressure which is lower than the atmospheric pressure in the condition where said on-off valve is open; and clogging determining means for closing said on-off valve at the time of completion of the pressure reduction by said pressure reducing means, and for determining that said charging passage is clogged between said pressure sensor and said fuel tank, wherein said clogging determining means determines that said charging passage is clogged between said pressure sensor and said fuel tank after closing said on-off valve.