An exhaust temperature raising apparatus has an exhaust
throttle valve that adjusts the engine exhaust amount based on the amount of throttling, and an
injector that performs main injection and a sub-injection directly into a cylinder, a combination of an ECU, the injection and the exhaust
throttle valve as
exhaust gas temperature increase apparatus for, during an engine warm-up, performing and controlling the exhaust throttling by the
exhaust valve and performing and controlling an
exhaust gas temperature increase through
combustion attributed to the main injection performed in an excess-air condition and
combustion attributed to the sub-injection, an
exhaust gas temperature sensor that monitors a state of temperature increase of the exhaust gas caused by performance of the exhaust gas temperature increase apparatus, and the ECU as monitor
abnormality detection apparatus for determining whether the exhaust gas temperature sensor has an
abnormality, and the ECU as exhaust gas temperature increase stop apparatus for stopping the operation of the exhaust gas temperature increase apparatus when the ECU determines that the exhaust gas temperature sensor has an
abnormality.