Patent ID: 9341544
Filing Date: 2016-05-17
CPC Classification: F01N,F02D,G01M,G01N,Y02T

Claim Text:
1. An abnormality detecting device of an internal combustion engine comprising: a sensor nick abnormality detecting unit configured to detect a nick abnormality in a detecting element of a downstream side sensor which is provided in a downstream side of an exhaust gas purifying catalyst in an exhaust passage of an internal combustion engine having a plurality of cylinders and generates an output corresponding to an oxygen concentration in exhaust gas, on the basis of an output of the downstream side sensor, the sensor nick abnormality detecting unit detecting the nick abnormality in the detecting element of the downstream side sensor on the basis of a matter that a distribution of the output of the downstream side sensor is biased to an area in which the air-fuel ratio is leaner than a theoretical air-fuel ratio; an inhibiting unit configured to inhibit detection of the nick abnormality of the detecting element by the sensor nick abnormality detecting unit in the case that an intake air amount exceeds a predetermined amount; a value calculating unit configured to calculate a value indicating a degree of air-fuel ratio variation between the cylinders on the basis of an output of an upstream side air-fuel ratio sensor provided on an upstream side of the exhaust gas purifying catalyst; a variation level detecting unit configured to detect that the degree of the air-fuel ratio variation between the cylinders is equal to or more than a predetermined level by comparing the value calculated by the value calculating unit with a predetermined value; and a second inhibiting unit configured to inhibit an operation of the inhibiting unit in the case that the variation level detecting unit does not detect that the degree of the air-fuel ratio variation between the cylinders is equal to or more than the predetermined level.