When the air fuel ratio dither control is carried out, an air fuel ratio of a mixture in each of one or more lean cylinders and one or more rich cylinders is controlled in a feedback manner based on an average value of a detected value of an air fuel ratio sensor, so that an average value of an air fuel ratio of exhaust gas flowing into the three-way catalyst becomes a predetermined target exhaust gas air fuel ratio. At this time, the air fuel ratio dither control is carried out, by setting at least a cylinder with the highest gas impingement intensity in a cylinder group of an internal combustion engine as the one or more lean cylinders.

A system includes an engine adapted to output a torque, a parasitic load adapted to receive a portion of the torque from the engine, and a controller communicably coupled to the parasitic load. The controller is configured to determine an actual exhaust temperature value of an exhaust gas flow exiting the engine and a minimum fuel amount to be injected into the engine. The controller is configured to compare the actual exhaust temperature value with an exhaust temperature threshold value of the exhaust gas flow to determine a first difference between the actual exhaust temperature value and the exhaust temperature threshold value. The controller is configured to determine a target torque output of the engine based on the first difference and the minimum fuel amount. The controller is configured to cause the torque to be increased to attain the target torque output using the parasitic load.

Methods and systems are provided for adjusting engine operation based on wirelessly received weather data in conjunction with engine sensor outputs. In one example, a method may comprise receiving a first measurement of a weather parameter from one or more engine sensors and a second measurement of the weather parameter from weather data, the weather data provided by a wireless weather service. The method may further comprise determining accuracies for the first and second measurements, generating an estimate of the weather parameter based on the accuracies of the first and second measurements, and adjusting at least one engine operating parameter based on the generated estimate.

A method includes receiving a signal indicative of a change in an air-fuel ratio (AFR) for a mixture of air and fuel entering a first combustion chamber of a combustion engine, advancing firing timing of the first combustion chamber, receiving, from a knock sensor, a knock signal indicating that the combustion engine has begun to knock, determining a knock margin of the first combustion chamber based on when the combustion engine begins to knock, and storing the knock margin as associated with the knock timing and the AFR.

Computational models and calculations relating to trapped and scavenged air per cylinder (APC) improve scavenging and non-scavenging operational modes of internal combustion engines as well as the transition there-between. Data from sensors which include engine speed, manifold air pressure, barometric pressure, crankshaft position, and valve state are provided to a pair of artificial neural networks. A first neural network utilizes this data to calculate the nominal volume of gas, i.e., air trapped in the cylinder. A second neural network utilizes this data to calculate the trapping ratio. The output of the first network is utilized with the ideal gas law to calculate the actual mass of trapped APC. The actual mass of trapped APC is also divided by the trapping ratio calculated by the second network to determine the total APC and is further utilized to calculate the scavenged APC by subtracting the trapped APC from the total APC.

The system, according to one embodiment of the present invention, comprises a stationary coil linear motor to drive a valve with a stem comprising a ferromagnetic property. The linear motor moves the valve in response to control governed by an electronic valve control computer. The valve is movable between a closed position at a selectable rate of both acceleration and speed for a selectable distance (“lift”) to a second selectable open position, including all position variations between the fully open and fully closed states. Valve position, velocity and acceleration can be varied both during a valve stroke and from one stroke to the next, as controlled by the logic programmed on a non-transitive memory of the electronic valve control computer.

The speed of a turbocharger may be estimated using data from sensors that are readily available in most engine management systems. In some cases, a pressure measurement from a MAP sensor may be used, in combination with one or more computational models, to provide an efficient, lower cost estimate of turbo speed that can be used to control operation of the engine and/or the turbocharger.

A control device includes an electronic control unit. The electronic control unit is configured to calculate an ignitionability index value and a combustion timing index value. The electronic control unit is configured to store relevant information defining a relationship between the ignitionability index value and the combustion timing index value, and a torque fluctuation limit value. The electronic control unit is configured to calculate a distance between a current operating point, which is specified by the ignitionability index value and the combustion timing index value, and a point on the torque fluctuation limit line. The electronic control unit is configured to retard ignition timing when the distance is larger than a threshold value, and enrich an air-fuel ratio and retard the ignition timing when the distance is equal to or smaller than the threshold value.

A vehicle control device includes an input unit configured to receive plural requests for a physical amount to be controlled in a vehicle; a judgment unit configured to judge whether or not a degree of priority of each of the received requests is high: a second mediation unit configured to, when there are plural requests whose degrees of priority are judged not to be high, mediate these plural requests to determine a control target value (Rm); a transfer unit configured to, when there is a request whose degree of priority is judged to be high, transfer this request as the control target value; and an output unit configured to output the control target value transferred from the transfer unit or determined by the second mediation unit to a VDC.

Various methods and arrangements for controlling catalytic converter temperature are described. In one aspect, an engine controller includes a catalytic monitor and a firing timing determination unit. The catalytic monitor obtains data relating to a temperature of a catalytic converter. Based at least partly on this data, the firing timing determination unit generates a firing sequence for operating the engine in a skip fire manner. Another aspect of the invention relates to an engine exhaust system that can help expedite the heating of a catalytic converter.