The objective of the present invention is to provide an engine with improved startability and stable operation regardless of the driving environment and usage conditions. The engine is equipped with a control means, which calculates a standard injection timing on the basis of the target rotational frequency of the engine and a standard injection amount, that is, the amount of fuel injected, and which corrects the standard injection timing using at least one correction amount. A fuel injection control unit calculates a cooling water correction amount on the basis of the target rotational frequency of the engine, the standard injection amount, and the cooling water temperature, and when the cooling water temperature is less than a first prescribed temperature the control unit corrects the standard injection timing using only the cooling water correction amount.

An engine system and method for improving sampling of a port throttle pressure sensor. In one example, the port throttle pressure sensor is sampled a plurality of times during a cylinder cycle and different engine operating conditions are determined from selected samples. The system and method may improve engine air-fuel control as well as engine diagnostics.

A fuel control system according to the principles of the present disclosure includes a voltage measuring module, a first difference module, a second difference module, a third difference module, and an injector driver module. The voltage measuring module measures first and second voltages at first and second electrical connectors of a fuel injector of an engine. The first difference module determines a first difference based on a difference between the first and second voltages. The second difference module determines a second difference between (i) the first difference and (ii) a previous value of the first difference. The third difference module determines a third difference between (i) the second difference and (ii) a previous value of the second difference. The injector driver module selectively applies power to the fuel injector based on the third difference.

A method for controlling a vehicle including an exhaust aftertreatment system for purifying exhaust gases from a compression-ignition engine includes monitoring vehicle operating parameters, determining whether the vehicle is stopped, determining whether the engine is commanded off, and determining whether the exhaust aftertreatment device is at a predetermined operating temperature. When the vehicle is stopped, the engine is commanded off and the exhaust aftertreatment device is at the predetermined operating temperature the engine is controlled in a run-on state for a predetermined period of time. The run-on state includes operating the engine in a throttled and fueled state.

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.

Methods and systems are provided for addressing pre-ignition occurring while operating with blow-though air delivery. A variable cam timing device used to provide positive intake to exhaust valve overlap is adjusted in response to an indication of pre-ignition to transiently reduce valve overlap. Pre-ignition mitigating load limiting and enrichment applied during a blow-through mode is adjusted differently from those applied when blow-through air is not being delivered.

The invention relates to a method for detecting the failure of injectors in an internal combustion engine, comprising the following steps: measuring a crank angle signal; transforming the crank angle signal into the frequency range by means of a discrete Fourier transformation; switching off each injector once and in a sequential manner; detecting and storing an angle of the harmonic of the 0.5th order of the Fourier-transformed crank angle signal for each switched-off injector once and in a sequential manner; continuous detection and storage of an angle and an amount of the harmonic of the 0.5th order of the Fourier-transformed crank angle signal; continuous comparison of the continuously detected amount with a predetermined threshold value, and determining a failure of the injector when the amount exceeds the predetermined threshold value; comparing the continuously detected angle with the angles stored for each switched-off injector when a failure of the injector is detected, and identifying the failed injector with an injector, for which a matching, stored angle is found.

In a control system for an internal combustion engine in which an exhaust gas purification catalyst having a lower catalyst layer and an upper catalyst layer disposed at the upper side of the lower catalyst layer is arranged in an exhaust passage of the internal combustion engine, when an operation at a rich air fuel ratio is switched to an operation at a target lean air fuel ratio, switching is made through a first operation in which the air fuel ratio of exhaust gas is temporarily made into a lean air fuel ratio, and a second operation which is carried out after the first operation and in which the air fuel ratio of the exhaust gas is made to change alternately between the rich air fuel ratio and the lean air fuel ratio a plurality of times, whereby the HC poisoning of the catalyst can be recovered at an early stage.

In an electronic control unit, a basic injection quantity calculation part calculates a basic injection quantity value as a target of fuel value, which an injector injects, by using an actual accelerator operation angle value, an actual engine rotation speed value and at least one of an actual vehicle speed value and an actual acceleration value. When the actual vehicle speed value or the acceleration value deviates largely from the estimated value, a correction value calculation part calculates an injection quantity correction value for the basic injection quantity value and a final injection quantity calculation part calculates a final injection quantity value by correcting the basic injection quantity value with the correction value. A driving control part controls driving of the injector so that the injector injects fuel of the final injection quantity value determined by correcting the basic injection quantity value with the correction value.

A fuel control system according to the principles of the present disclosure includes a parameter determination module, a parameter learning module, and an injector driver module. The parameter determination module determines a parameter of a fuel injector in an engine at an operating condition of the engine. The parameter learning module identifies index values in a table based on the engine operating condition and adjusts learned values of the fuel injector parameter corresponding to the index values based on the determined value of the fuel injector parameter. The injector driver module selectively applies power to the fuel injector based on the learned values.