Patent ID: 9261052
Filing Date: 2016-02-16
CPC Classification: F01P,F02B,F02D,F02M,Y02T

Claim Text:
1. A failure diagnosis apparatus of an EGR system comprising a pipe member and an EGR cooler linked to the pipe member and configured to recirculate part of exhaust gas discharged into an exhaust system of an internal combustion engine to an intake system via the pipe member and the EGR cooler, said failure diagnosis apparatus comprising: an electronic control unit configured to: receive a pressure difference between upstream side pressure and downstream side pressure of the EGR cooler from a pressure difference sensor; compare a pressure difference value detected by the pressure difference sensor with a predetermined cooler blocking determination value and a predetermined pipe blocking determination value that is smaller than the cooler blocking determination value; and determine that, when the pressure difference value detected is greater than the cooler blocking determination value, blocking occurs in an inside of the EGR cooler, and determine that, when the pressure difference value detected is smaller than the pipe blocking determination value, blocking occurs in an inside of the pipe member, wherein a location of the blocking is written to the electronic control unit.