System comprising an internal combustion engine including a crankshaft, a crankshaft sprocket coupled to the crankshaft, an electric motor in mechanical communication with the crankshaft sprocket, a bidirectional engine position sensor coupled to the crankshaft sprocket, a controller in electrical communication with the bidirectional engine position sensor and a non-transitory memory having instructions that, in response to execution by a processor, cause the processor to determine a position of an engine component upon shutdown of the engine, store the position of the engine component at shutdown in the non-transitory memory, and control the electric motor at restart in response to the position of the engine component at shutdown are disclosed. Methods are also disclosed.

A catalyst control system includes a stop and start module that, during a period that the vehicle is ON between (i) a first time when the vehicle is turned ON and (i) a second time when the vehicle is next turned OFF, selectively shuts down and starts a spark ignition engine of the vehicle. A catalyst light off (CLO) control module initiates a first CLO event for a first engine startup during the period and, when a temperature of a catalyst that receives exhaust output by the engine is less than a predetermined temperature, selectively initiates a second CLO event for a second engine startup during the period. A fuel control module richens fueling of the engine during the first and second CLO events of the period. A spark control module retards spark timing of the engine during the first and second CLO events of the period.

A method for starting an internal combustion engine (ICE) having a crankshaft and an electric turning machine (ETM) operatively connected to the crankshaft comprises energizing an absolute position sensor adapted for providing an indication of an angular position of a rotor of the ETM and applying a current to the ETM to generate a sufficient torque to rotate the crankshaft.

A system and method for an electronic control unit adapter used to supplement existing electronic control units for enhanced or additional IO integration, the electronic control unit adapter designed to be updated easily by the end user in order to add functionality as it is developed thus prolonging the viability of an electronic control unit or vehicle, the electronic control unit adapter usable in conjunction with a vehicle or other vessel using an internal combustion engine or similar technology.

A misfire determination period is set to a predetermined range of a crank angle. A CPU performs: a calculation process of calculating an average value of a torque of an output shaft of an internal combustion engine in the misfire determination period; a misfire determining process of determining that a misfire has occurred when the calculated average value is less than a prescribed threshold value; and a process of setting the whole misfire determination period to a period in a positive torque range which is a range of a crank angle at which the torque of the output shaft is equal to or greater than zero at the time of normal combustion in which a misfire does not occur.

In an engine starting system, a first controller activates, in response to a driver's starting request, a first starting device to rotate the rotating shaft of an engine. A second controller is communicably connected to the first controller. The second controller recognizes rotation of the rotor of a second starting device resulting from an activation of the first starting device. The second controller starts a power running operation of the second starting device based on the recognition of the rotation of the rotor. The first controller determines whether the power running operation of the second starting device has been started. The first controller deactivates, when it is determined that the power running operation has been started, the first starting device before a rotational angular position of the rotating shaft of the engine arrives at a compression top dead center of the engine.

A method for operating an engine during a fuel cut-off mode is disclosed. The method may adjust exhaust valve opening timing and exhaust valve lift of one or more cylinders to heat air flowing through the one or more cylinders so that a temperature of an after treatment device may be maintained or increased.

A diagnostic system for a vehicle includes a difference module, a Fourier module, and a fault module. The difference module determines pressure differences for a camshaft revolution based on differences between: first pressures within first chambers of a camshaft phaser measured during the camshaft revolution, wherein the first pressures within the first chamber control advancement of the camshaft relative to a crankshaft of an engine; and second pressures within second chambers of the camshaft phaser measured during the camshaft revolution, wherein the second pressures within the second chamber control retardation of the camshaft relative to the crankshaft of the engine. The Fourier module performs a Fourier Transform (FT) based on the pressure differences to produce FT data. The fault module, based on the FT data, selectively indicates that a fault is present in a variable valve lift mechanism that is actuated by the camshaft.

Systems and methods determining a presence or absence of engine misfire at low engine load are disclosed. In one example, the presence or absence of engine misfire is based on a fuel target error value and an exhaust temperature error. Operation of an engine may be adjusted when engine misfire is detected.

Some embodiments described herein relate to a method of operating a compression ignition engine. The method of operating the compression ignition engine includes opening an intake valve to draw a volume of air into a combustion chamber, closing an intake valve, and moving a piston from a bottom-dead-center (BDC) position to a top-dead-center (TDC) position in the combustion chamber at a compression ratio of at least about 15:1. The method further includes injecting a volume of fuel into the combustion chamber at an engine crank angle between about 330 degrees and about 365 degrees during a first time period. The fuel has a cetane number less than about 40. The method further includes combusting substantially all of the volume of fuel. In some embodiments, a delay between injecting the volume of fuel into the combustion chamber and initiation of combustion is less than about 2 ms.