Abstract: A misfire detecting apparatus is provided wherein a misfire is detected based on a rotational speed parameter indicative of a rotational speed of an internal combustion engine. An average change amount of the rotational speed parameter in a first predetermined period and an inertia speed changing component which is generated with rotation of the engine are calculated, and a first corrected rotational speed parameter is calculated by correcting the rotational speed parameter according to the average change amount and the inertia speed changing component.

Abstract: Some embodiments are directed to a variable displacement controller for use with a vehicular engine. The controller can receive data indicative of ambient temperature and data indicative of at least one of engine speed and vehicle speed. The controller can determine engine torque value based on the engine speed, and determine a torque limit based on the ambient temperature and at least one of the determined engine torque value and the data indicative of vehicle speed. The controller can compare the engine torque value to the torque limit, and selectively activate/deactivate an engine cylinder based on the comparison between the engine torque value and the torque limit, such that the engine cylinder is deactivated if the engine torque value is less than the torque limit, and the engine cylinder is activated if the engine torque value is greater than or equal to the torque limit.

Abstract: Some embodiments are directed to a variable displacement controller for use with a vehicular engine. The controller can receive data indicative of ambient temperature and data indicative of at least one of engine speed and vehicle speed. The controller can determine engine torque value based on the engine speed, and determine a torque limit based on the ambient temperature and at least one of the determined engine torque value and the data indicative of vehicle speed. The controller can compare the engine torque value to the torque limit, and selectively activate/deactivate an engine cylinder based on the comparison between the engine torque value and the torque limit, such that the engine cylinder is deactivated if the engine torque value is less than the torque limit, and the engine cylinder is activated if the engine torque value is greater than or equal to the torque limit.

Abstract: A misfire detecting apparatus is provided wherein a misfire is detected based on a rotational speed parameter indicative of a rotational speed of an internal combustion engine. An average change amount of the rotational speed parameter in a first predetermined period and an inertia speed changing component which is generated with rotation of the engine are calculated, and a first corrected rotational speed parameter is calculated by correcting the rotational speed parameter according to the average change amount and the inertia speed changing component.