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.

A control device for a compression-ignition engine in which partial compression-ignition combustion including spark ignition (SI) combustion performed by combusting a portion of a mixture gas inside a cylinder by spark-ignition followed by compression ignition (CI) combustion performed by causing the remaining mixture gas to self-ignite is executed at least within a part of an engine operating range is provided, which includes a detector configured to detect a given parameter that changes as combustion progresses inside the cylinder, an A/F (air-fuel ratio) controller configured to change an air-fuel ratio of air to fuel introduced into the cylinder, and a combustion controller configured to determine combustion stability based on the detected parameter of the detector and control the A/F controller to reduce the air-fuel ratio when it is confirmed that during the partial compression-ignition combustion the combustion stability is low.

A method for operating an internal combustion engine having an injection system which has a high-pressure accumulator, wherein a high pressure in the high-pressure accumulator is regulated via a suction throttle on the low-pressure side as a first pressure control member in a first high-pressure control loop, wherein in a normal operation a high-pressure disturbance variable is produced via a pressure control valve on the high-pressure side as a second pressure control member, via which fuel is redirected from the high-pressure accumulator to a fuel reservoir. For this purpose, the high pressure in a safety operation is regulated by the pressure control valve via a second high-pressure control loop, or, in the safety operation, a maximum fuel volume flow is continuously redirected from the high-pressure accumulator to the fuel reservoir via the pressure control valve.

A method for checking a measurement of pressure in a fuel tank, implemented in a vehicle having a fuel tank and a fuel vapor breather circuit including: a filter, a tank isolation valve interposed between the tank and the filter, and a purge line, connected to the filter, downstream thereof, a pressure sensor, and a purge valve. The method includes, when the purge valve is closed: measuring a value of the pressure in the tank when the isolation valve is closed, then measuring a temporal extreme value for the pressure in the purge line following an opening of the isolation valve, and determining, from the measured values, that there is an anomaly in the measured pressure in the tank.

Various embodiments include a method comprising: moving a piston toward TDC in successive pump cycles; during the movement, closing an inlet valve by applying current to an electromagnet; generating a pressure signal downstream of the outlet; applying a measurement current to the electromagnet when the inlet valve is closed; while the piston moves away from TDC, detecting an opening position at which an opening movement of the inlet valve begins on the basis of a predetermined change with respect to time of the measurement current; checking whether a value sequence of the ascertained opening positions over multiple pump cycles satisfies a predetermined discrepancy criterion with regard to the sensor signal; and if the discrepancy criterion is satisfied, generating a fault signal relating to the pressure sensor.

A pressure sensor malfunction determination device for a fuel tank includes a fuel tank that stores fuel, a canister that absorbs an evaporated fuel gas and includes a drain port opened to atmosphere, an evaporation path communicating with the canister and fuel tank, a purge gas path communicating with an engine inlet system and the canister, a pressure sensor that detects a pressure, a solenoid valve that opens/closes the evaporation path, and a control unit that controls an opening/closing state of the solenoid valve. When the fuel tank pressure is one of predetermined positive and negative pressure states, the control unit performs valve-opening control on the solenoid valve. The control unit includes a pressure sensor malfunction determination unit that, when an output value of the pressure sensor detected under an atmospheric pressure condition corresponds to a pressure other than the atmospheric pressure, determines that the pressure sensor is malfunctioning.

Systems and methods for diagnosing operation of a sensor of an exhaust system are presented. In one example, the systems and methods may diagnose operation of the sensor when an engine is combusting air and fuel. Further, operation of the sensor may be diagnosed when the engine is not combusting air and fuel so that vehicle occupants may not be disturbed by the diagnostic.

A failure diagnosis system for an in-cylinder pressure sensor is provided, which includes an in-cylinder pressure sensor, a fuel injection valve, an engine controller including an engine control module and a diagnosis module. The engine control module controls the fuel injection valve to stop the supply of fuel to the engine, when a fuel cut condition is satisfied while the automobile travels. The diagnosis module includes a limiting module configured to limit an execution of the failure diagnosis of the in-cylinder pressure sensor until the diagnosis module determines that a given period has lapsed after the stop of fuel supply to the engine. The diagnosis module reads a signal of the in-cylinder pressure sensor when the given period has lapsed after the stop of the fuel supply to the engine, and diagnoses the failure of the in-cylinder pressure sensor based on the read signal of the in-cylinder pressure sensor.

A failure diagnosis device for an in-cylinder pressure sensor is provided, which includes an in-cylinder pressure sensor, and an engine controller comprised of circuitry configured to execute a diagnosis module into which a signal of the sensor is inputted, to diagnose a failure of the sensor based on the signal. The diagnosis module includes a reading module configured to read the signal of the sensor within a specific crank angle range, a reference phase determining module configured to determine a reference phase that is a phase of a pressure change accompanying a volume change of the combustion chamber, and a failure determining module configured to determine that the sensor has failed, when the failure determining module determines a phase of the read signal of the sensor is delayed by an amount exceeding a predefined threshold from the determined reference phase.

Various embodiments include a method for checking a calibration of a pressure sensor comprising: moving a piston toward a TDC in successive cycles; while the piston moves toward TDC, closing an inlet valve thereby adjusting a setpoint value of a fluid pressure; measuring the fluid pressure with the pressure sensor arranged downstream of the outlet valve; applying a measurement current to the electromagnet when the inlet valve is closed; while the piston moves away from TDC, detecting an opening position of the inlet valve on the basis of a predetermined change with respect to time of the measurement current at which an opening movement of the inlet valve begins; over multiple pump cycles, changing the setpoint value of the fluid pressure by a predetermined difference; checking whether the change in opening position satisfies a predetermined correspondence criterion; and if the criterion is met, generating a fault signal.