Abstract: A fuel property determining device for an engine is provided, which retards a fuel injection timing and determines a fuel property based on a combustion variation of the engine caused by the retarding. The device includes a first determining module for setting a retarding amount to a first setting amount at an early stage of the fuel property determination, and in a case where the variation is above a first given value when the first amount is set, suspending the retarding and determining that the fuel property is a first fuel property, and a second determining module for setting the retarding amount to a second setting amount in a case where the variation is below the first given value when the first amount is set, and determining the fuel property based on the variation caused when the second amount is set, the second amount being larger than the first amount.

Abstract: A diesel engine for a vehicle comprises an engine body mounted in the vehicle having a plurality of cylinders that is supplied with fuel, a plurality of fuel injection valves for directly injecting the fuel into the cylinders, and an injection control module for controlling a mode of injecting the fuel into the cylinders through the fuel injection valves. The injection control module sets a fuel injection amount per cylinder at least according to a load on the engine body, performs a main injection, and performs at least one pre-injection where fuel is injected prior to the main injection. The injection control module further executes a cylinder-cutoff operation mode where the fuel supplies to the cylinder or the cylinders are stopped when the engine body is under a low load condition where the fuel injection amount per cylinder is below a predetermined amount.