摘要 |
When switching the fuel to be used for engine operation from gasoline to CNG, in a state where CNG is supplied experimentally to one cylinder serving as a judgment object and gasoline is supplied to other cylinders, whether or not CNG can be supplied to the cylinder serving as a judgment object is judged based on an amount of change ”Pc in fuel pressure inside a CNG delivery pipe (Step S13 to Step S16). When it is judged that a gas fuel can be supplied to all cylinders (Step S19: YES), the fuel to be used for engine operation is switched from the liquid fuel to the gas fuel (Step S20). |