A method of implementing control logic of a compression-ignition engine is provided. A controller outputs a signal to a injector and a variable valve operating mechanism so that a gas-fuel ratio (G/F) becomes leaner than a stoichiometric air fuel ratio, and an air-fuel ratio (A/F) becomes equal to or richer than the stoichiometric air fuel ratio, and to an ignition plug so that unburnt mixture gas combusts by self-ignition after the ignition plug ignites mixture gas inside a combustion chamber. The method includes steps of determining a geometric compression ratio and determining the control logic defining an intake valve close timing IVC. IVC (deg.aBDC) is determined so that the following expression is satisfied: if the geometric compression ratio is 10<17,

0.4234.sub..sup.222.926.sub.+207.84+CIVC0.4234.sub..sup.2+22.926.sub.167.84+C

where C is a correction term according to an engine speed NE (rpm),

C=3.310.sup.10NE.sup.31.010.sup.6NE.sup.2+7.010.sup.4NE.

A method of determining a condition of a component (e.g., valves) of an engine having a manifold air pressure sensor during a cold test includes providing pressurized air to an intake of the engine. The method includes rotating a crankshaft of the engine. The method includes measuring pressures with the manifold air pressure sensor as a function of crankshaft rotational position. The method includes comparing the pressures with a predetermined baseline. The method includes indicating a condition of the component based on the comparison of the pressures with the baseline.

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.

A method of controlling intake and exhaust cam phase in an internal combustion engine includes sensing an engine speed and an engine load of the internal combustion engine, sensing or estimating a wall temperature of a cylinder of the internal combustion engine, utilizing the engine speed and the engine load in one or more lookup tables based on the cylinder wall temperature to determine intake phaser constraint values and exhaust phaser constraint values for cold operation of the internal combustion engine, and transitioning the intake phaser constraint values and the exhaust phaser constraint values for cold operation to intake phaser constraint values and exhaust phaser constraint values based on one or more lookup tables for normal hot operation of the internal combustion engine.

An exhaust heat recovery system. The system includes a heat exchanger configured to transfer heat from engine exhaust to a heat transfer fluid. A reservoir is in fluid communication with the heat exchanger. A pump is configured to pump the heat transfer fluid out of the heat exchanger and into the reservoir, and in doing so displace air out of the reservoir to the heat exchanger, when temperature of the heat transfer fluid exceeds a predetermined temperature.

Methods and systems are provided for reducing release of undesired emissions to atmosphere at a start event of an engine configured to propel a vehicle. In one example, a method comprises providing an alternative heat source and actively routing heat from the alternative heat source to a heated exhaust gas oxygen sensor for which a heating element configured to raise temperature of the sensor is known to be degraded. In this way, a desired air-fuel ratio may be attained during engine start events where the heating element for raising temperature of the sensor is degraded, which may thus reduce tail-pipe emissions which may otherwise be released in the absence of such mitigating action.

Methods and systems are provided for compression heating of air. In one example, a method may include, during an engine start and prior to a first combustion event, deactivating cylinder exhaust valves while spinning the engine electrically and unfueled until a threshold intake air temperature is reached, and alternately activating and deactivating the exhaust valves of one or more cylinders to maintain the intake air temperature above the threshold temperature after the first combustion event. In this way, a temperature of an air charge may be increased, resulting in increased fuel economy and decreased vehicle emissions.

Provided is a control device for controlling an internal combustion engine including a fuel injection valve, an ignition device, and a variable valve operating device configured to switch between a base opening/closing mode of an intake valve and a continuous valve opening mode. The control device is configured to execute a cold start control at a cold start. The cold start control includes: a startability improvement processing executed in a predetermined number of cycles after the start of cranking; and a combustion start processing executed after this predetermined number of cycles. In the startability improvement processing, the continuous valve opening mode is selected in at least an expansion stroke and an exhaust stroke, and fuel injection is executed without ignition. In the combustion start processing, the base opening/closing mode is selected continuously during one cycle, and ignition is executed.

A number of variations may include a method comprising controlling the combustion phase timing in the first firing cycle of a start/stop combustion engine comprising: providing a camshaft operatively connected to an extended range intake cam phaser; fully or partially retarding the extended range intake cam phaser during an engine restart to control a position of the camshaft and prevent pre-ignition; and retarding a spark timing in the first cylinder to delay the combustion phase timing to improve NVH.

A system and method for cylinder deactivation in a multi-cylinder diesel engine comprises pumping air in to an intake manifold of the diesel engine using a turbocharger. Air is pumped in to the intake manifold using an intake air assisting device. And, fuel injection is selectively deactivated to at least one of the cylinders in the diesel engine. An intake valve and an exhaust valve is selectively deactivated for the at least one of the cylinders of the diesel engine.