An apparatus and a method are provided for an oil filter-leak pressure-test station. The oil filter-leak pressure-test station comprises an air pump, a pressure gauge, a vent valve, an overflow reservoir, and a manifold configured to receive an oil filter. The oil filter-leak pressure-test station is configured to apply a desired internal air pressure to an oil filter for observing the oil filter assembly for any potential leaks, such as along a seal ring, rolled seam or a nut-end. The oil filter-leak pressure-test station is also configured to be mounted in a vise or similar mechanical attachment for observation to determine the extent or existence of any leak in the oil filter. The oil filter-leak pressure-test station may also be submerged in water using a submersion reservoir, so as to determine the existence and location of any leaks.

A variety of methods and arrangements for detecting failure of the commanded air induction in an internal combustion engine are described. In some embodiments, the intake manifold pressure is monitored. An air induction event generates a fluctuation in the intake manifold pressure, which is recorded. The signal is processed through a diagnostic filter to help determine whether the actual induction matched the commanded induction. In other embodiments, measured crankshaft acceleration is compared with estimated crankshaft acceleration. If the two quantities differ by a threshold amount an induction fault is detected. The two detection methods may also be combined. The describe approaches are particularly well suited for use in engines operating in a skip fire mode with cylinder deactivation and/or a dynamic firing level modulation mode.

A variety of methods and arrangements for detecting failure of the commanded air induction in an internal combustion engine are described. In some embodiments, the intake manifold pressure is monitored. An air induction event generates a fluctuation in the intake manifold pressure, which is recorded. The signal is processed through a diagnostic filter to help determine whether the actual induction matched the commanded induction. In other embodiments, measured crankshaft acceleration is compared with estimated crankshaft acceleration. If the two quantities differ by a threshold amount an induction fault is detected. The two detection methods may also be combined. The describe approaches are particularly well suited for use in engines operating in a skip fire mode with cylinder deactivation and/or a dynamic firing level modulation mode.

Computational models and calculations relating to trapped and scavenged air per cylinder (APC) improve scavenging and non-scavenging operational modes of internal combustion engines as well as the transition there-between. Data from sensors which include engine speed, manifold air pressure, barometric pressure, crankshaft position, and valve state are provided to a pair of artificial neural networks. A first neural network utilizes this data to calculate the nominal volume of gas, i.e., air trapped in the cylinder. A second neural network utilizes this data to calculate the trapping ratio. The output of the first network is utilized with the ideal gas law to calculate the actual mass of trapped APC. The actual mass of trapped APC is also divided by the trapping ratio calculated by the second network to determine the total APC and is further utilized to calculate the scavenged APC by subtracting the trapped APC from the total APC.

Computational models and calculations relating to trapped and scavenged air per cylinder (APC) improve scavenging and non-scavenging operational modes of internal combustion engines as well as the transition there-between. Data from sensors which include engine speed, manifold air pressure, barometric pressure, crankshaft position, and valve state are provided to a pair of artificial neural networks. A first neural network utilizes this data to calculate the nominal volume of gas, i.e., air trapped in the cylinder. A second neural network utilizes this data to calculate the trapping ratio. The output of the first network is utilized with the ideal gas law to calculate the actual mass of trapped APC. The actual mass of trapped APC is also divided by the trapping ratio calculated by the second network to determine the total APC and is further utilized to calculate the scavenged APC by subtracting the trapped APC from the total APC.

The present disclosure relates to internal combustion engines and the teachings thereof may be embodied in methods and apparatus for detecting a malfunctioning rail pressure sensor. Some embodiments may include a method for detecting a malfunctioning rail pressure sensor comprising: delivering an analog output signal characterizing the rail pressure to a control unit; generating a differential rail pressure signal as a digital output signal; delivering the differential rail pressure signal of the rail pressure sensor to the control unit; analyzing the analog output signal and the differential rail pressure signal in the control unit; and detecting a malfunctioning rail pressure sensor based on the analysis by the control unit.

The present disclosure relates to internal combustion engines and the teachings thereof may be embodied in methods and apparatus for detecting a malfunctioning rail pressure sensor. Some embodiments may include a method for detecting a malfunctioning rail pressure sensor comprising: delivering an analog output signal characterizing the rail pressure to a control unit; generating a differential rail pressure signal as a digital output signal; delivering the differential rail pressure signal of the rail pressure sensor to the control unit; analyzing the analog output signal and the differential rail pressure signal in the control unit; and detecting a malfunctioning rail pressure sensor based on the analysis by the control unit.

An electronic control unit diagnoses leakage abnormality in an intake system downstream from a supercharger provided in the intake system of the engine. The electronic control unit sets, as a supercharging region monitoring value, a ratio between a first air amount obtained from a detection value of an air flowmeter and a second air amount obtained from a detection value of an intake pressure sensor, the ratio being the ratio obtained when the engine is operated in a supercharging region. The electronic control unit also sets, as a non-supercharging region monitoring value, a ratio obtained when the engine is driven in a non-supercharging region. The electronic control unit determines the presence of the leakage abnormality in the intake system when the ratio of the supercharging region monitoring value to the non-supercharging region monitoring value is larger than a predetermined specified value.

An electronic control unit diagnoses leakage abnormality in an intake system downstream from a supercharger provided in the intake system of the engine. The electronic control unit sets, as a supercharging region monitoring value, a ratio between a first air amount obtained from a detection value of an air flowmeter and a second air amount obtained from a detection value of an intake pressure sensor, the ratio being the ratio obtained when the engine is operated in a supercharging region. The electronic control unit also sets, as a non-supercharging region monitoring value, a ratio obtained when the engine is driven in a non-supercharging region. The electronic control unit determines the presence of the leakage abnormality in the intake system when the ratio of the supercharging region monitoring value to the non-supercharging region monitoring value is larger than a predetermined specified value.

Methods and systems are provided for detecting a fuel tank oil-canning event during conditions when a vacuum is applied to the fuel tank, such as during a fuel system leak test or during purging of a fuel system canister. In one example, a method may include comparing the fuel tank pressure changes during a leak test to changes in fuel tank temperature or fill level and indicating fuel tank oil-canning in response to a higher than threshold rise in fuel tank pressure during or following application of vacuum to the fuel tank while each of a fuel temperature and fill level remain unchanged. By detecting fuel tank oil-canning accurately, appropriate countermeasures can be taken.