Methods and systems are provided for detecting air-fuel ratio imbalances across all engine cylinders. In one example, a method (or system) may include indicating cylinder imbalance based on each of the exhaust air-fuel ratio, exhaust manifold pressure, and cylinder torque weighted by a confidence factor, where in the confidence factor is determined based on operating conditions.

A target air amount for achieving a requested torque is back-calculated from the requested torque using a parameter that provides a conversion efficiency of an air amount to torque. The value of the parameter gradually changes to lower the conversion efficiency as the requested torque decreases from a second reference value towards a first reference value. The first reference value is calculated based on the engine speed. The second reference value is calculated based on an air amount with which the first reference value is achieved under a second air-fuel ratio, and a first air-fuel ratio. The target air-fuel ratio is set to the first air-fuel ratio when the requested torque is greater than the first reference value, and is switched from the first air-fuel ratio to the second air-fuel ratio when the requested torque decreases to a value equal to or less than the first reference value.

A method of controlling fuel injection in an internal combustion engine having at least one cylinder with an associated fuel injector for performing injection events is proposed, wherein for each injection event a pulse width is determined with which the injector is kept open to spray a desired quantity of fuel. When the quantity of fuel of a given fuel injection event is greater than a learning threshold, a split fuel injection is performed, whereby a first, low injection pulse and a second, complementary injection pulse are executed. Data representative of a closing time and/or an opening time of the fuel injector is determined in respect of the first, low injection pulse and a learned correction value is elaborated based on the closing time and/or opening time, the learned correction value being subsequently used for injection control.

An engine includes a control means that calculates a standard injection time based on the target number of revolutions of the engine and a standard injection amount being a fuel injection amount of the engine and corrects the standard injection time based on at least a correction amount, and a fuel injection control unit calculates a coolant correction amount based on the target number of revolutions, the standard injection amount, and a coolant temperature of the engine, and when the coolant temperature is less than a first predetermined temperature, the fuel injection control unit corrects the standard injection time only based on the coolant correction amount.

A forklift includes a hydraulic pump being a variable displacement pump driven by an engine, a hydraulic motor driven with fluid from the pump, a storage storing first and second groups, and a predetermined lift pressure setting value, the first group including output characteristics each representing relation between a rotational speed of the engine and a torque of the engine for each lift pressures, the second group including output characteristics each representing relation between the rotational speed and the torque for each pump pressures, and determining a greater one of first and second torques as a target torque of the engine, the first torque being calculated from one selected from the first group using the lift pressure setting value or an actual lift pressure and the rotational speed, the second torque being calculated from one selected from the second group using the pump pressure and the rotational speed.

A control system for an engine of a vehicle includes an adder module that determines a pressure sum based on a sum of a plurality of pressures determined based on (i) a plurality of operating parameters of the vehicle and (ii) a plurality of predetermined values calibrated for determining an estimated pressure at a location within an exhaust system of the vehicle. An estimating module determines the estimated pressure at the location within the exhaust system based on the pressure sum and a reference pressure. An actuator control module selectively adjusts at least one engine actuator based on the estimated pressure.

In an internal combustion engine, gaseous fuel is injected in a first injection through a pre-combustion chamber into the combustion chamber to mix with air in the combustion chamber. The pre-combustion chamber has a jet aperture in fluid communication between the pre-combustion chamber and the combustion chamber. Mixed gaseous fuel and air is then ingested into the pre-combustion chamber from the combustion chamber and ignited. In a second injection, injecting gaseous fuel into the pre-combustion chamber and expelling, with the second injection, ignited gaseous fuel and air from the pre-combustion chamber through the jet aperture and into the combustion chamber as a flaming jet with a core of gaseous fuel.

A system according to the principles of the present disclosure includes a model predictive control (MPC) module and an actuator module. The MPC module generates a set of possible target values for an actuator of an engine and predicts an operating parameter of the engine for each of the possible target values. The MPC module determines a weighting value associated with each of the target values based on a corresponding iteration number and determines a cost for the set of possible target values based on the predicted operating parameters and the weighting values. The MPC module selects the set of possible target values from multiple sets of possible target values based on the cost and sets target values to the possible target values of the selected set. The actuator module controls an actuator of an engine based on at least one of the target values.

A method is provided for operating a vehicular engine that comprises a plurality of pistons and a plurality of cylinders. The method comprises detecting an engine temperature and detecting an alcohol concentration of fuel. The method further comprises selecting an amount of fuel according to the engine temperature and the alcohol concentration and selectively dispensing the amount of fuel to the cylinders.

The disclosure relates to a method for operating an internal combustion engine having a plurality of cylinders, the method comprising, during one working cycle, distributing fuel for each cylinder of the plurality of cylinders among a plurality of injection processes according to settable split factors which respectively define a setpoint fuel mass and/or injection duration and time setting of each respective injection process for the plurality of individual injection processes, wherein random variation is carried out for at least one injection process.