A control system includes a controller. The controller counts the number of driving times of a high pressure fuel pump, which is the number of reciprocating motions of a plunger based on a crank counter. The controller estimates a high pressure system fuel pressure based on the calculated number of driving times, a fuel temperature detected by a fuel temperature sensor, and a low pressure system fuel pressure detected by a low pressure system fuel pressure sensor when the high pressure system fuel pressure is not able to be acquired from a high pressure system fuel pressure sensor. The controller sets an opening period of an in-cylinder fuel injection valve based on the estimated high pressure system fuel pressure and to perform an engine start by an in-cylinder fuel injection when the high pressure system fuel pressure is not able to be acquired from the high pressure system fuel pressure sensor.

Disclosed is a method for controlling an engine torque for a diesel engine, characterized in that the engine torque control is implemented in an injection system. The injection system in question includes a high-pressure pump controlled by an engine control unit, the high-pressure pump supplying a fuel supply rail, the pump being dimensioned to be capable of delivering a capacity volume of compressible fuel for each combustion cycle of the diesel engine. It also includes a pressure sensor for measuring the pressure of the fuel in the fuel rail.

A fuel injection control method for an internal combustion engine is provided. The internal combustion engine includes a fuel pump (38) that pressure-feeds fuel, a fuel injection valve (19) that injects the fuel pressure-fed by the fuel pump directly into a cylinder of the internal combustion engine (1), and a fuel pressure detection device (45) that detects a pressure of the fuel pressure-fed by the fuel pump. The fuel injection control method executes a first smoothing process (S3) of performing a smoothing process on a detected fuel pressure by first smoothing, a second smoothing process (S4) of performing a smoothing process on the detected fuel pressure by second smoothing different from the first smoothing, and a selection process (S5) of selecting, based on an operating state of the internal combustion engine, whether to execute fuel injection control (S6, S7) based on a first detected fuel pressure smoothed by the first smoothing process or fuel injection control (S8, S9) based on a second detected fuel pressure smoothed by the second smoothing process.

Methods and systems for adjusting fuel injector operation according to changes in fuel pressure during inter-injection periods are described. The inter-injection period may be before and after fuel is injected to an engine. The methods and systems described herein may be suitable for direct and port fuel injectors.

A control system includes a controller. The controller acquires a crank counter value each time a fixed time elapses. The controller calculates the number of the crank counter values corresponding to the top dead center of the plunger between a previously acquired crank counter value and a currently acquired crank counter value with reference to the map each time the crank counter value is acquired and calculate the number of driving times of the high pressure fuel pump by integrating the calculated number.

Methods and systems for adjusting fuel injector operation according to changes in fuel pressure during inter-injection periods are described. The inter-injection period may be before and after fuel is injected to an engine. The methods and systems described herein may be suitable for direct and port fuel injectors.

Methods and systems are provided for reducing errors in estimated fuel rail pressure incurred at the time of a scheduled injection event due to engine-driven cyclic fuel rail pressure changes. In one example, a pulse-width commanded during a scheduled injection event is determined as a function fuel rail pressure samples collected over a moving window that is customized for the corresponding fuel injector. In another example, the commanded pulse-width is determined as a function of an average fuel rail pressure sampled during a quiet zone of injector operation and predicted fuel rail pressure altering events occurring between the quiet zone and the scheduled injection event.

A storage device is configured to store a first mapping that receives, as an input, a first input variable including a cam phase variable on present and past phases of a cam, and output a pulsating variable on a pulsating component. The execution device is configured to acquire the first input variable and estimate the pulsating variable by applying the acquired first input variable to the first mapping. Therefore, it is possible to estimate the pulsating variable without providing a low-pressure fuel pressure sensor by estimating a fuel pressure variable by applying the first input variable to the first mapping.

Methods and systems are provided for tracking a fuel puddle mass in the intake port of a deactivated engine cylinder. The difference in fuel evaporation rate in the deactivated cylinder intake is accounted for by applying distinct time constant and gain values to a transient fuel compensation model. A fuel vapor content is clipped once the intake vapor pressure in the intake port of the deactivated cylinder reaches a saturation pressure limit.

A control system includes a controller. The controller estimates the swing-back amount indicating the turning amount of the crankshaft in the reverse rotation direction until the crankshaft stops. The controller calculates a stop-time counter value which is a value of a crank counter at the time when the engine is stopped based on a final counter value which is the value of the crank counter calculated last before the crankshaft stops and the estimated swing-back amount. The controller corrects the swing-back amount used for calculating the stop-time counter value based on a difference between the number of driving times calculated with reference to the map based on the calculated stop-time counter value and the value of the crank counter and the number of driving times calculated by increasing the number of driving times by one each time the high pressure system fuel pressure increases by the threshold or more.