ENGINE, CONTROL DEVICE, AND CONTROL

An engine includes a cylinder, a piston, an ignition device, a rotation sensor, an intake temperature sensor, an intake pressure sensor, and a control device. The ignition device ignites a gas mixture. The rotation sensor measures the rotation speed of a crankshaft. The intake temperature sensor measures the temperature of the gas mixture. The intake pressure sensor measures a first pressure value of the gas mixture. The control device controls the hydrogen equivalent ratio of hydrogen contained in the gas mixture and/or timing of igniting the gas mixture based on the rotation speed, the temperature of the gas mixture, and the first pressure value of the gas mixture.