Described herein is a process for designing a virtual sensor that is able to estimate a variable of interest v as a function of a set of available variables u.sub.i. The process comprises the steps of: acquiring (1002) a design data-set D.sub.d comprising a number N of measured values v(ti) of the variable of interest v and corresponding measured values i(ti) of the available variables u.sub.i; determining a limit on the disturbances of the available variables u.sub.i and a limit on the errors of the method of measurement of the variable of interest v; selecting (1004) a Lipschitz function * with a respective Lipschitz constant , which is able to estimate the variable of interest v(t) as a function of a number n of past values of each available variable u.sub.i, by executing the following steps one or more times for different numbers n: a) determining a value for the Lipschitz constant y; b) defining (1006) a maximum limit (r(t)) and a minimum limit (r(t)) for the estimate of the variable of interest v as a function of the design data-set D.sub.d, and moreover the number n, the value for the Lipschitz constant y, the limit on the disturbances of the available variables u.sub.i, and the limit on the errors of the method of measurement of the variable of interest v, and choosing a Lipschitz function * comprised between the maximum limit (r(t)) and the minimum limit (r(t)); c) determining (1008) an estimation error *(*) for the Lipschitz function * and selecting the Lipschitz function *, associated to which is a respective Lipschitz constant y* and a respective number n*, that presents the minimum estimation error *(*(y*, n*)); and implementing (1012) the selected Lipschitz function * in an electronic circuit.

Methods and systems are provided for refilling a fuel tank devoid of fuel vapors. In one example, a method may include, prior to an upcoming refueling event, conditioning a fuel vapor-less fuel tank by operating a fuel pump. Operation of the fuel pump may agitate and vaporize the residual fuel in the fuel tank.

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.

Methods and systems are provided for diagnosing an exhaust waste-gate valve via an electric boost assist motor of an electric turbocharger. Degradation of the waste-gate valve is inferred based on the motor torque profile of the motor after commanding the waste-gate valve to an open or closed position on a torque transient. Deviation of the motor torque profile from the expected profile is used to infer if the valve is stuck open or closed, and actions are taken accordingly.

Disclosed is a method for detecting the direction of rotation of a crankshaft of an engine of a motor vehicle. The detection method includes in particular, when the crankshaft is in a second predetermined angular position between a low angular position and a high angular position of the crankshaft, a step of commanding the closure of a control valve for the intake of fuel into the high-pressure pump, a step of measuring a second pressure value in the high-pressure rail, and a step of detecting a nominal direction of rotation of the crankshaft if the second pressure value measured is greater than or equal to an expected pressure value or of detecting a reverse direction of rotation of the crankshaft if the second pressure value measured is less than the expected pressure value.

Methods and systems are provided for an integrated fuel composition-pressure sensor. In one example, the integrated sensor may include a set of cylindrical capacitors and a set of plate capacitors with a common capacitor element shared between the sets. A composition of fuel may be determined from the set of cylindrical capacitors and a pressure of fuel may be determined from the set of plate capacitors.

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.

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.

A control system includes a controller. The controller counts the number of driving times of the high pressure fuel pump, which is the number of the reciprocating motions of the plunger based on a crank counter that is counted up at every predetermined crank angle. The controller stores a map in which a top dead center of the plunger is associated with a crank counter value, and store a crank counter value while an engine is stopped as a stop-time counter value. The controller calculates, referring to the map, the number of the crank counter values corresponding to the top dead center of the plunger between a crank counter value and the stop-time counter value, and set a calculated number as the number of driving times.

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.