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.