Abstract: When the ratio of the amount of vaporized fuel (purge amount) to be introduced into an intake passage of an engine from a fuel tank through a purge passage pipe, a purge control valve, etc. to the total amount of fuel (total fuel amount) to be supplied to the engine is large, an abnormality determination system acquires, as a parameter Pon, the air-fuel ratio imbalance index value that increases as the difference between the air-fuel ratios of the respective cylinders increases. When the purge amount is small relative to the total fuel amount, the determination system acquires the air-fuel ratio imbalance index value as a parameter Poff. When the difference between the parameters Pon and Poff is less than a predetermined value and at least one of these parameters is greater than a predetermined threshold value, the determination system determines that an inter-cylinder air intake amount variation abnormality is occurring.

Abstract: The invention relates to a method for regulating a stationary gas motor (1). In said method, a deviation of the regulated speed is calculated from a desired speed and an actual speed, a desired moment is determined as an adjustable variable from the deviation of the regulated speed by means of a speed governor, said desired moment being limited to an air ratio-limiting moment by limiting the moment, and a desired volume flow (VSL) is determined from the limited desired moment in order to define an angle (DKW1, DKW2) of the mixture throttle valve and an angle of the gas throttle valve.

Abstract: A variable valve timing controller for an internal combustion engine includes a hydraulic variable valve timing unit, a lock pin, and a hydraulic control valve. The lock pin is configured to lock the VCT phase at an intermediate lock position. The variable valve timing controller controls a valve drive electric current that is used for actuating the hydraulic control valve. The controller controls the valve drive electric current based on a first control characteristic in the operation of the hydraulic control valve under a first control range. The controller controls the valve drive electric current based on a second control characteristic in the operation of the hydraulic control valve under a second control range. The first control characteristic is different from the second control characteristic.

Abstract: An inter-cylinder air-fuel-ratio imbalance determination apparatus includes an air-fuel-ratio sensor in an exhaust passage of an engine. The air-fuel-ratio sensor functions as a limiting-current-type wide range air-fuel-ratio sensor when a voltage is applied, and functions as a concentration-cell-type oxygen concentration sensor when no voltage is applied. The determination apparatus causes the air-fuel-ratio sensor to function as the limiting-current-type wide range air-fuel-ratio sensor, and executes air-fuel ratio feedback control on the basis of the output value of the air-fuel-ratio sensor. When an imbalance determination parameter is obtained, the determination apparatus causes the air-fuel-ratio sensor to function as the concentration-cell-type oxygen concentration sensor, and obtains, as the imbalance determination parameter, a value corresponding to the differentiated value of the output value of the air-fuel-ratio sensor.

Abstract: A dynamic feedforward amount to realize a predetermined transient response characteristic by compensating a transient response characteristic of an engine having a Variable Nozzle Turbo (VNT) and an Exhaust Gas Recirculator (EGR) is calculated for a nozzle opening degree of the VNT and a valve opening degree of the EGR. The transient response characteristic of the engine responds to a setting value of an injection quantity or the like. Then, command values of the nozzle opening degree of the VNT and the valve opening degree of the EGR are calculated by using the dynamic feedforward amount. In the transient state, the followingness to the target value is improved.

Abstract: A computer-implemented method is used to correct deviations between a predicted gas excess air ratio and a calculated excess air ratio in a dual fuel engine or other gas fueled compression ignition engine. The method includes determining gas excess air ratio for the engine based at least in part on at least one detected current operating parameter and calculating a predicted exhaust gas oxygen concentration engine based on the predicted gas excess air ratio. A time based filtered predicted exhaust gas oxygen concentration value may then be calculated and compared to a time-based filtered measured exhaust gas oxygen concentration value. The resultant oxygen concentration deviation value may be used to generate a corrected predicted gas excess air ratio.

Abstract: In one embodiment, a common rail fuel system for an engine of a vehicle, such as a locomotive, comprises a higher-pressure fuel sub-system and a lower-pressure fuel sub-system, wherein a pressure limiting valve, is in fluid communication with to the higher-pressure fuel sub-system to relieve excess pressure. In a condition where pressure of the higher-pressure fuel sub-system is below a desired and expected threshold, it is possible that the pressure limiting valve is open. An example method is provided to close the pressure limiting valve and determine if opening of the pressure limiting valve is the cause of the pressure being below the threshold or if a leak is present in the common rail fuel system. In this manner, unnecessary disabling of the engine is avoided and, if a leak is present, the leaking sub-system is identified.

Abstract: A diagnostic system for an engine includes an error detection module and a diagnostic module. The error detection module selectively detects a fuel control error based on a change in a fuel correction value used to determine a quantity of fuel supplied directly to an exhaust system. The diagnostic module identifies a cause of the fuel control error based on a period since a last refueling event. The diagnostic module identifies the cause as one of variation in an actual heating value of the fuel and faulty operation of a fuel injection system that supplies the fuel. The diagnostic module further identifies the cause based on a first amount of the fuel contained in a fuel tank at a start of the last refueling event and a second amount of the fuel added to the fuel tank during the last refueling event. A control system and method are also provided.

Abstract: A fuel consumption amount evaluation system is disclosed. The system includes a rotational speed detecting section (5b) for detecting an engine rotational speed of the engine-driven traveling vehicle as a measured rotational speed, an accelerator opening degree detecting section (5a) for detecting an accelerator opening degree, a fuel injection amount calculating means (50) for calculating a fuel injection amount per predetermined unit from the accelerator opening degree and the measured rotational speed, and a mileage evaluating section (54) for effecting a mileage evaluation based on the fuel injection amount calculated by the fuel injection amount calculating means (50).

Abstract: A method for operating at least one injector of an internal combustion engine, in which a voltage applied to the injector is varied, and a rotational speed pattern of the internal combustion engine is ascertained as a function of the voltage, a setpoint voltage, suitable for operating the at least one injector, corresponding to that varied applied voltage for which a peak arises in a spectrum of the rotational speed pattern.

Abstract: There is provided an internal EGR control device for an internal combustion engine, which, even when a change in the actual valve timing of exhaust valves is caused by aging, is capable of properly controlling an internal EGR amount while compensating for an adverse influence caused by the change, and thereby properly controlling the temperature within the cylinder. The internal EGR control device 1 sets a target internal EGR amount EGRINCMD which serves a target of the internal EGR amount, according to detected operating conditions, NE and PMCMD, of the engine 3, and calculates internal energy QACT possessed by burned gases, which is determined according to the amount and temperature of the burned gases. Further, the target internal EGR amount EGRINCMD is corrected according to the calculated internal energy, and the valve-closing timing of the exhaust valve 9 is calculated according to the corrected internal EGR amount EGRIN.