A control apparatus for an internal combustion engine includes an electronic control unit that is configured to perform an operation of making a lift amount of a specific valve corresponding to one of either intake ports or exhaust ports for a specific cylinder in which an amount of condensate water produced in the port or flowing into the port is larger than in the other cylinders when the engine is stopped, in a case where production of condensate water in the ports or inflow of condensate water into the ports is predicted.

In a control device for an engine, the engine includes combustion chambers, ports connected to the combustion chambers, and valves that open and close areas between the combustion chambers and the ports. The control device includes an electronic control unit that is configured to execute an anti-freezing operation of performing control to fully close the valves or make the valves be in a state of being opened with a lift amount of 1 mm or more, in a case where temperatures around the valves are lowered to a predetermined temperature range after the engine is stopped, or in a case where an outside air temperature when the engine is stopped is equal to or lower than a predetermined temperature. The predetermined temperature range is a temperature range in which an upper limit value is lower than 10 C., and the predetermined temperature is lower than 5 C.

In a control device for an engine, the engine includes combustion chambers, ports connected to the combustion chambers, and valves that open and close areas between the combustion chambers and the ports. The control device includes an electronic control unit that is configured to execute an anti-freezing operation of performing control to fully close the valves or make the valves be in a state of being opened with a lift amount of 1 mm or more, in a case where temperatures around the valves are lowered to a predetermined temperature range after the engine is stopped, or in a case where an outside air temperature when the engine is stopped is equal to or lower than a predetermined temperature. The predetermined temperature range is a temperature range in which an upper limit value is lower than 10 C., and the predetermined temperature is lower than 5 C.

Methods and systems are described for an engine with a cam torque actuated variable cam timing phaser. Phaser positioning control is improved by reducing inaccuracies resulting from inadvertent spool valve and/or phaser movement when the spool valve is commanded between regions. In addition, improved spool valve mapping is used to render phaser commands more consistent and robust.

Methods and systems are provided for providing exhaust gas recirculation to a naturally aspirated internal combustion engine. In one example, exhaust gas is recirculated to an engine intake via a dedicated scavenging manifold and a scavenging exhaust valve. The exhaust gas and fresh air that has not participated in combustion may be recirculated to engine cylinders even at high engine loads since the exhaust gas and fresh air is returned to the engine air intake at a pressure greater than atmospheric pressure.

A method for operating a combustion engine after a cold start, the combustion engine including a supercharger device, a plurality of combustion chambers, a fuel-injection device injecting into each of the combustion chambers, and a gas-exchange valve control device that controls gas-exchange valves in a variable manner. A rich fuel-air mixture is generated in the combustion chambers, and the combustion-chamber charges are ignited in a retarded manner. Following the cold start, the combustion engine is operated with first valve overlaps that are greater than in a warm combustion engine. A first exhaust valve of a first combustion chamber is initially closed at such a late point that its opening duration overlaps with the opening duration of a second exhaust valve of a second combustion chamber that directly follows the first combustion chamber in the ignition sequence and that discharges into the same exhaust manifold as the first combustion chamber.

In a control device for an engine, the engine includes combustion chambers, ports connected to the combustion chambers, and valves that open and close areas between the combustion chambers and the ports. The control device includes an electronic control unit that is configured to execute an anti-freezing operation of performing control to fully close the valves or make the valves be in a state of being opened with a lift amount of 1 mm or more, in a case where temperatures around the valves are lowered to a predetermined temperature range after the engine is stopped, or in a case where an outside air temperature when the engine is stopped is equal to or lower than a predetermined temperature. The predetermined temperature range is a temperature range in which an upper limit value is lower than 10? C., and the predetermined temperature is lower than 5? C.

In a control device for an engine, the engine includes combustion chambers, ports connected to the combustion chambers, and valves that open and close areas between the combustion chambers and the ports. The control device includes an electronic control unit that is configured to execute an anti-freezing operation of performing control to fully close the valves or make the valves be in a state of being opened with a lift amount of 1 mm or more, in a case where temperatures around the valves are lowered to a predetermined temperature range after the engine is stopped, or in a case where an outside air temperature when the engine is stopped is equal to or lower than a predetermined temperature. The predetermined temperature range is a temperature range in which an upper limit value is lower than 10? C., and the predetermined temperature is lower than 5? C.

A method can include controlling, by at least one controller, an amount of hydrocarbons provided upstream of a diesel oxidation catalyst. The method can include determining, by the at least one controller, a first temperature of exhaust gas at an inlet of the diesel oxidation catalyst. The exhaust gas can be produced from combustion of fuel. The method can include determining, by the at least one controller, a second temperature of the exhaust gas at an outlet of the diesel oxidation catalyst. The method can include calculating, by the at least one controller, a lower heating value of the fuel based on the first temperature, the second temperature, the amount of hydrocarbons, and a flow rate of the exhaust gas. The method can include estimating, by the at least one controller, a percentage of biodiesel in the fuel based on the lower heating value.

A fuel control module controls fuel injection of an engine based on a predetermined lean air/fuel ratio. The predetermined lean air/fuel ratio is fuel lean relative to a stoichiometric air/fuel ratio for the fuel. A cylinder control module selectively deactivates opening of intake and exhaust valves of M cylinders of the engine to increase removal of nitrogen oxide (NOx) from exhaust. M is an integer greater than 0 and less than a total number of cylinders of the engine. The fuel control module further: disables fueling of the M cylinders while opening of the intake and exhaust valves of the M cylinders is deactivated; and, while fueling of the M cylinders is disabled and opening of the intake and exhaust valves of the M cylinders is deactivated, controls fuel injection of other cylinders based on a predetermined rich air/fuel ratio that is fuel rich relative to the stoichiometric air/fuel ratio.