Systems and methods to extend a life of a component of a cylinder deactivation system are provided. A method includes initiating, by a controller, a CDA mode for an engine; determining, by the controller, a first cycle count for a first oil control solenoid of the CDA system; determining, by the controller, a second cycle count for a second oil control solenoid of the CDA system; comparing, by the controller, the first cycle count and the second cycle count; and modifying, by the controller, operation of the CDA mode for the engine based on the comparison.

Systems and related methods for regulating fuel rail pressure for internal combustion engines utilizing an electronic fuel transfer pump (eFTP) on the low side to provide robust control of fuel pressure on the high side. The eFTP is in fluid communication with a low-pressure fuel circuit for providing a low-pressure fuel flow at a low pressure to a high-pressure pump. Upon failure of a fuel control valve, a pressure-responsive valve, and/or a pressure sensor impacting the high-side fuel pressure, the eFTP modulates the low-side fuel flow and/or low-side fuel pressure to mitigate damage to the engine. A controller in operative communication with the eFTP and/or one or more sensors is configured to provide a pump command to the eFTP in response to a failure condition impacting the high-side fuel pressure.

A locomotive engine control system includes one or more processors operably connected to fuel supply devices. The fuel supply devices are configured to supply fuel into different corresponding cylinders of an engine. The one or more processors are configured to monitor a fuel quantity injected into the cylinders of the engine before and after communication of an overfuel control signal. The overfuel control signal commands the fuel supply device corresponding to a first cylinder of the cylinders to supply excess fuel into the first cylinder. Responsive to the fuel quantity that is monitored not decreasing after the communication of the overfuel control signal, the one or more processors are configured to determine that the fuel supply device corresponding to the first cylinder is defective, and may generate one or more control signals indicative of the fuel supply device corresponding to the first cylinder being defective.

Methods and systems are provided for enabling a transfer function of a direct injector and a port injector, each fueling an engine cylinder, to be accurately learned. During selected conditions, the direct injected fuel fraction may be actively changed from a target fraction to one of an upper and lower limit of the direct injector so as to provide a measurable air-fuel ratio error. Fueling errors for the distinct fuel injectors is then learned based on the measured air-fuel ratio error relative to the actively changed fuel fraction.

A method is described for diagnosing errors in an internal combustion engine in which fuel is injected from a high-pressure accumulator into associated combustion chambers with the aid of multiple fuel injectors, a first value (R.sub.stat,2) which is representative of a static flow rate of fuel through one of the fuel injectors being ascertained, a second value (n) which is representative of a running smoothness of the internal combustion engine being ascertained, if at least one of the two values (R.sub.stat,2, n) deviates from the particular associated reference value (R.sub.stat, n.sub.0), an error (F) being deduced, and the error (F) being assigned to the fuel injector and/or at least one further component and/or at least one operating phase of the internal combustion engine on the basis of deviations of the two representative values (R.sub.stat,2, n) from the particular associated reference value (R.sub.stat, n.sub.0).

A method for extracting characterizing features from an ion current trace retrieved from spark plugs of cylinders of an internal combustion engine, comprises the steps of: i. dividing the ion current signal into crank angle subintervals; ii. calculating a measure of ion current in each crank angle subinterval; and iii. Performing a calculation on the measure of ion currents from different subintervals such that the result of the calculation is dimension free. Further it relates to a method of monitoring combustion processes where a plurality of ion current signals from a number of spark plugs (4A, 4B) are retrieved and used in combination.

The present disclosure relates generally to system and method for detecting fuel shutoff valve failures in a system including multiple fuel shutoff valves connected in series. By commanding different fuel shutoff valves to close and detecting changes in the system operating conditions, the system and method may determine if any of the fuel shutoff valves are not working properly.

A system includes a reciprocating engine having a piston disposed in a cylinder, an intake valve, an exhaust valve, and an exhaust flow path downstream of the exhaust valve. The system also includes a first sensor configured to obtain a first feedback indicative of an exhaust gas parameter in the exhaust flow path. The system also includes a controller configured to identify a valve wear condition of at least one of the intake valve or the exhaust valve at least partially based on the first feedback from the first sensor.

Systems and methods utilize a controller configured to perform a diagnostic routine for a combustion seal provided between a gasoline direct injection (GDI) fuel injector and a combustion chamber of a cylinder of a GDI engine. The diagnostic routine comprises determining one of (i) a period for the injector coil current to reach a peak current and (ii) a resistance of the injector coil while the injector coil current is saturated, determining whether the determined period or the determined injector coil resistance is greater than a respective threshold indicative of a predetermined temperature of the injector coil, and when the determined period or the determined injector coil resistance is greater than its respective threshold, detecting a combustion seal leak fault. Based on the combustion seal leak fault, the controller may modify operation of the engine to prevent potential heat damage to the engine.

Methods and systems are provided for diagnosing a degraded fuel injector delivering undesired additional fuel in a variable displacement engine. In one example, a method includes, responsive to an indication of a cylinder air-fuel imbalance, deactivating a subset of cylinders of a multi-cylinder engine, performing a power balance test to determine an output of each cylinder after a duration of deactivation, and indicating that a deactivated cylinder has a degraded fuel injector responsive to the output being lower than a threshold output.