A method and system for operating a two-stroke engine includes a fuel system comprising a fuel pressure sensor, fuel temperature sensor and a fuel injector and a controller in communication with the fuel pressure sensor and fuel temperature sensor. The controller controls the fuel injector with a fuel pulsewidth determined by determining a beginning time of a window for measuring fuel pressure, determining an ending time of the window, measuring fuel pressure between the beginning time and the ending time, determining a fuel pulsewidth based on the fuel pressure and fuel temperature and injecting fuel into the two-stroke engine in response to a desired fuel mass.

A method includes: determining that at least one cylinder of a first cylinder bank of an engine is active; determining that at least one cylinder of a second cylinder bank of the engine is inactive; receiving an inlet temperature of a selective catalytic reduction system; comparing the inlet temperature to a temperature setpoint; and adjusting at least one of a first exhaust manifold pressure setpoint for the first cylinder bank or a second exhaust manifold pressure setpoint for the second cylinder bank based on the comparison.

A method for determining a combination of an actual intake camshaft phase position of an intake camshaft and an actual exhaust camshaft phase position of an exhaust camshaft of a production internal combustion engine having at least one cylinder, wherein the method is performed in operation of the production internal combustion engine and the relevant actual phase position of the camshafts is determined in relation to an operating point of the production internal combustion engine.

A vent insert is disclosed for use with an automotive turbocharger system. The vent has a substantially cylindrical hollow tube with a first end for seating the vent and a second open end. The first end has a rim around an opening. The second end of the vent has an angled opening that faces away from the direction of the gas flow when the vent insert is operating within the turbocharger system. There are a plurality of protrusions extending outward from the outside surface of the vent to assist in keeping the vent insert in place in the turbocharger system.

Systems, methods, and apparatuses are provided for increasing exhaust gas temperature. A system includes a valve and a controller coupled to the valve. The controller is structured to determine that a plurality of cylinders of an engine are active; compare an exhaust aftertreatment temperature to an exhaust aftertreatment temperature setpoint; and in response to the comparison, adjust an effective flow area for exhaust gas from the plurality of cylinders of the engine to increase an exhaust gas temperature.

A system includes a fuel tank and a dehydration reactor that are configured to provide a primary fuel and a pilot fuel to a power system. The fuel tank is configured to store the primary fuel and is fluidly connected to a reactor feed line and a primary fuel line provide the primary fuel. The dehydration reactor is configured to receive the primary fuel via the reactor feed line and convert a portion of the primary fuel to the pilot fuel and a byproduct. The power system is configured to receive the pilot fuel from the dehydration reactor to initiate combustion of the primary fuel. The power system also includes a cylinder with an internal piston that receives the pilot fuel and the primary fuel, contains the combustion reaction, and generates power from the combustion reaction; and contains the combustion reaction. A pilot fuel injector provides the pilot fuel to the cylinder at a first time to initiate combustion and a primary fuel injector provides the pilot fuel to the cylinder at to generate power via the power system.

A diagnostic system and method that (a) that uses models indicative of both successful firing and skips to determine if cylinders of a skip fire controlled internal combustion engine have successfully fired or successfully skipped and (b) uses filtered exhaust gas pressure readings for detecting faults associated with EGR systems and/or turbocharger systems.

Various methods and systems are provided for a multi-fuel capable engine. The system includes a liquid fuel system to deliver liquid fuel to an engine, a gaseous fuel system to deliver gaseous fuel to the engine, and a control system. The control system can control and test the liquid and gaseous fuel systems.

An engine test method that causes a computer to execute a process including, acquiring, by a processer on the computer, a first test pattern in which an operation variable that is used for an engine test is changed in time series, inputting, based on the first test pattern, a first operation variable to a mathematical model that represents a time series response of an engine obtained by inputting a test pattern as a simulation of the engine test, monitoring, as a first monitoring parameter of engine abnormality, at least one of an air excess ratio, pressure and temperature of an intake manifold, pressure and temperature of an exhaust manifold, and a maximum cylinder pressure rise rate that are obtained by inputting the first operation variable to the mathematical model, holding, when the first monitoring parameter exceeds a first threshold value, the first operation variable until the first monitoring parameter is less than the first threshold value, creating, a history of the first operation variable in the simulation as a second test pattern, monitoring, as a second monitoring parameter, at least one of the air excess ratio, the pressure and the temperature of the intake manifold, the pressure and the temperature of the exhaust manifold, and the maximum cylinder pressure rise rate that are obtained by inputting a second operation variable to a real engine based on the second test pattern, holding, when the second monitoring parameter exceeds a second threshold value, the second operation variable until the second monitoring parameter is less than the second threshold value, and acquiring, time series data of the second operation variable and a controlled variable.

Methods and systems are provided for diagnostics of exhaust gas recirculation (EGR) components including an EGR pressure sensor. In one example, a method for an exhaust gas recirculation (EGR) system of a vehicle comprises diagnosing an excessive EGR flow rate via an MAP-MAF strategy, the MAP-MAF strategy including estimating an EGR flow rate based on a difference between an output of a manifold absolute pressure (MAP) sensor of the vehicle and an output of a mass airflow (MAF) sensor of the vehicle; and in response to stable intrusive conditions being met, intrusively commanding an EGR valve of the EGR system to a closed position to confirm the diagnosed excessive EGR flow rate. If the excessive flow is detected after the EGR valve is commanded to the closed position, a diagnostic code may be set.