Disorder diagnosis method for fuel system of vehicle because of fuel's overflowing

摘要

The present invention relates to a fuel overflow fault diagnosis method of the fuel system for an automobile, and more particularly fuel is based devices due to the leakage of the fuel shut-off valve on the overflow canister of fuel or fuel overflow connection fault diagnosis of automotive fuel systems to diagnose problems that accumulate on the line. ; For this purpose, The present invention includes the steps of determining whether the fuel meets the diagnostic approach overflow condition; Evaporation gas control device comprising the steps of: determining whether or not normal in the case that satisfies the entering condition diagnosis fuel overflow; The method comprising: determining whether the boil-off gas control apparatus for diagnosing condition is satisfied in the normal case; Comprising the steps of: determining the concentration of the canister is greater than the concentration threshold in the case of satisfying the diagnosing condition; Determining the concentration of the canister is greater than the rich (rich) determination threshold value is greater than the amount of fuel learning in concentration threshold; The fuel amount learning value failure determination counter (counter) is greater than the rich determining threshold value is increased, and the failure determination counter is greater than the deterioration determining step of determining a threshold value; The failure determining step determines that the fuel counter is deceased between the fuel tank and the canister is greater than the failure decision threshold; provides a fuel overflow fault diagnosis method of the fuel system for a car, characterized in that comprises a