| 摘要 |
PURPOSE:To enable alarming of abnormality to a driver, by providing an abnormality detecting means and an alarm generating means which are actuated when an output from an oxygen sensor located in an intake air passage running between an EGR passage and an engine body is beyond an allowable range. CONSTITUTION:An oxygen sensor 18 is additionally located to an intake air manifold 2 between an EGR passage 11 and an engine body 1. In an EGR control circuit 19, when an output from an oxygen sensor 18 is beyond an allowable range responding to a desired EGR rate previously stored according to the operating state of an engine detected by a number of revolutions detector 8 and a boost detector 10, an abnormality detecting means generated an output. By means of the output, an alarm generating means 20 is actuated. This constitution enables abnormality, e.g., deterioration, failure in operation, of the EGR device to be alarmed to a driver without any delay. |
