Abstract: An engine control system comprises a fuel quality calculation module and a fueling module. The fuel quality calculation module calculates a fuel quality value for fuel provided to an engine based on at least one operating parameter of the engine. The fueling module selectively increases an amount of fuel provided to the engine based on the fuel quality value.

Abstract: A fuel injector diagnostic system includes a fuel pump control module, a pressure sensor, and a diagnostic module. The fuel pump control module disables delivery of fuel to a fuel rail of an engine. The pressure sensor measures a first pressure of the fuel rail before an injection event and a second pressure of the fuel rail after the injection event on at least one of a plurality of injectors when the engine is running. The diagnostic module diagnoses a fault in the at least one of the injectors based on the first pressure and the second pressure.

Abstract: An adaptive fuel delivery control system includes a pressure monitoring module and a flow rate determination module. The pressure monitoring module determines an actual pressure drop after a fuel injection event on an injector. The flow rate determination module determines an adjusted flow rate based on a reference flow rate and the pressure drop.

Abstract: A valve lifter control system includes a valve lifter control module and a forced transition determination module. The valve lifter control module determines a desired lift state of a valve lifter based on at least one of engine speed and engine load. The forced transition determination module initiates a forced transition of the valve lifter from the low-lift state to the high-lift state based on manifold vacuum independently of the desired lift state.

Abstract: A diagnostic system includes a first pressure monitoring module, a second pressure monitoring module, and a fault determination module. The first pressure monitoring module determines low-lift pressures and high-lift pressures in a cam phaser when a first oil control valve (OCV) moves first valve lifters to the low-lift state and the high-lift state, respectively. The second pressure monitoring module determines low-lift pressures and high-lift pressures in the cam phaser when a second OCV moves second valve lifters to the low-lift state and the high-lift state, respectively. The fault determination module diagnoses a fault in one of the first OCV and the second OCV based the low-lift pressures and the high-lift pressures.

Abstract: A lift mechanism diagnostic system comprises a fuel pump disabling module, a pressure module, and a diagnostic module. The fuel pump disabling module selectively disables a fuel pump that is driven by a camshaft. The pressure module determines a first pressure of fluid provided to a variable valve lift mechanism when the variable valve lift mechanism is operated in a first lift mode while the fuel pump is disabled and determines a second pressure of the fluid when the variable valve lift mechanism is operated in a second lift mode while the fuel pump is disabled. The diagnostic module selectively diagnoses a fault in the variable valve lift mechanism based on the first and second pressures.

Abstract: A system includes a pressure signal adjustment module that generates a maximum pressure signal based on a fluid pressure signal from a pressure sensor of a camshaft phaser system of an engine. The pressure signal adjustment module detects a maximum peak value of the fluid pressure signal and maintains the maximum pressure signal at the maximum peak value for a peak and hold period. A diagnostic module detects a fault of the camshaft phaser system based on the maximum pressure signal during the peak and hold period.

Abstract: A diagnostic system for an engine includes a phaser control module that commands a first cam phaser position of a cam phaser of the engine for a first period and a second cam phaser position of the cam phaser for a second period, and a phaser diagnostic module that diagnoses a phaser control error for the cam phaser based on a first pressure of fluid supplied by an oil control valve to the cam phaser measured during the first period, and a second pressure of fluid supplied by the oil control valve to the cam phaser measured during the second period. The first and second pressures are measured on one of an advance-side fluid chamber and a retard-side fluid chamber of the cam phaser. The phaser diagnostic module detects one of a phaser mechanical fault and a phaser hydraulic system fault. A related method is also provided.

Abstract: A control system for a powertrain of a vehicle includes a torque module and a damping control module. The torque module determines a first output torque and a second output torque of the engine. The second output torque is determined after the first output torque. The torque module also determines a torque difference based on the first output torque and the second output torque. The damping control module generates a damping torque in a transmission based on the torque difference.

Abstract: An engine mode control system for an internal combustion engine includes a transition control module and an intake cam phaser control module. The transition control module controls a transition from a first engine mode to a second engine mode and determines a desired air mass. The engine is operated at a first air/fuel ratio (AFR) in the first engine mode and at a second AFR in the second engine mode. The desired air mass is based on the second AFR. The intake cam phaser control module adjusts the intake cam phaser based on the desired air mass during the transition.

Abstract: A method and control module includes a control hold duty cycle module generating a control hold duty cycle signal and a voltage correction module generating a voltage correction signal. The control module also includes a correction module generating a corrected proportional correction signal based on a proportional correction signal and the voltage correction signal, and generating a corrected integral correction signal based on an integral correction signal and the voltage correction signal. The control module also includes a force determination module controlling a duty cycle to a phaser operator based upon the control hold signal, the corrected proportional correction signal and the corrected integral correction signal.

Abstract: A diagnostic system includes a first pressure monitoring module, a second pressure monitoring module, and a fault determination module. The first pressure monitoring module determines low-lift pressures and high-lift pressures in a cam phaser when a first oil control valve (OCV) moves first valve lifters to the low-lift state and the high-lift state, respectively. The second pressure monitoring module determines low-lift pressures and high-lift pressures in the cam phaser when a second OCV moves second valve lifters to the low-lift state and the high-lift state, respectively. The fault determination module diagnoses a fault in one of the first OCV and the second OCV based the low-lift pressures and the high-lift pressures.

Abstract: An engine control system comprises a camshaft, a cam phaser module, a pressure sensor, and an engine control module. The camshaft is operably coupled to a crankshaft of an engine. Rotation of the camshaft operates a fuel pump in driving communication with a cam of the camshaft. The cam phaser module provides hydraulic pressure to change a rotational position of the cam about the camshaft. The pressure sensor determines a cam phaser pressure signal based on a pressure of fluid in the cam phaser module. The engine control module diagnoses a condition of the fuel pump based on the cam phaser pressure signal.

Abstract: A lift mechanism diagnostic system comprises a fuel pump disabling module, a pressure module, and a diagnostic module. The fuel pump disabling module selectively disables a fuel pump that is driven by a camshaft. The pressure module determines a first pressure of fluid provided to a variable valve lift mechanism when the variable valve lift mechanism is operated in a first lift mode while the fuel pump is disabled and determines a second pressure of the fluid when the variable valve lift mechanism is operated in a second lift mode while the fuel pump is disabled. The diagnostic module selectively diagnoses a fault in the variable valve lift mechanism based on the first and second pressures.

Abstract: An engine control system comprises a fuel pump control module and a diagnostic module. The fuel pump control module controls a pressure pump to inject fuel into a fuel rail. The diagnostic module determines an estimated pressure increase within the fuel rail based on the injected fuel, compares an actual pressure increase within the fuel rail to the estimated pressure increase, and indicates when the actual pressure increase is less than the estimated pressure increase.

Abstract: An engine control system comprises a camshaft, a cam phaser module, a pressure sensor, and an engine control module. The camshaft is operably coupled to a crankshaft of an engine. Rotation of the camshaft operates a fuel pump in driving communication with a cam of the camshaft. The cam phaser module provides hydraulic pressure to change a rotational position of the cam about the camshaft. The pressure sensor determines a cam phaser pressure signal based on a pressure of fluid in the cam phaser module. The engine control module diagnoses a condition of the fuel pump based on the cam phaser pressure signal.

Abstract: A fuel control system for an engine includes a control module that includes a fuel rail pressure module and a comparison module. The fuel rail pressure module determines a first fuel rail pressure of a fuel rail after a first event and a second fuel rail pressure of the fuel rail after a second event. The first event includes N conditions, a first of the N conditions comprises deactivation of a fuel pump of the engine, and N is an integer. The second event includes M conditions, a first of the M conditions comprises activation of a fuel injector, and M is an integer. The comparison module adjusts a fuel injector constant of the fuel injector based on the first fuel rail pressure, the second fuel rail pressure, and an injector activation period corresponding to the second event.

Abstract: A control system and method for controlling a fuel system of an engine includes a steady state determination module determining the engine is operating at a steady state and a memory storing a first fuel correction. A fuel pump control module commands a predetermined fuel rail pressure change. The memory stores a second fuel correction after the predetermined fuel rail pressure change. A sensor error correction module determines a fuel rail pressure sensor error based on the first fuel correction and the second fuel correction and determines a fuel rail pressure in response to the sensor error.

Abstract: A method may include commanding operation of an engine in a first lift mode. The engine may include a valve lifter system that selectively operates a valve member in the first lift mode and a second lift mode through engagement with a camshaft. A first duty cycle of a cam phaser oil control valve (OCV) may be determined to maintain a first camshaft position corresponding to the first lift mode. The camshaft position may be maintained by a cam phaser that is coupled to the camshaft and in communication with the cam phaser OCV. Engine operation may be commanded to the second lift mode and a second duty cycle of the cam phaser OCV may be determined to maintain a second camshaft position corresponding to the second lift mode. A valve lifter system failure may be diagnosed based on a difference between the first and second duty cycles.

Abstract: A fuel control system for an engine includes a control module that includes a fuel rail pressure module and a comparison module. The fuel rail pressure module determines a first fuel rail pressure of a fuel rail after a first event and a second fuel rail pressure of the fuel rail after a second event. The first event includes N conditions, a first of the N conditions comprises deactivation of a fuel pump of the engine, and N is an integer. The second event includes M conditions, a first of the M conditions comprises activation of a fuel injector, and M is an integer. The comparison module adjusts a fuel injector constant of the fuel injector based on the first fuel rail pressure, the second fuel rail pressure, and an injector activation period corresponding to the second event.