A control device for an internal combustion engine is provided that can detect the adherence of deposits to a cylinder pressure sensor without subjecting the internal combustion engine to an impact or the like. A control device for an internal combustion engine equipped with a cylinder pressure sensor detects changes in the sensitivity of the cylinder pressure sensor. If the control device detects a decrease in the sensitivity of the cylinder pressure sensor after detecting an increase in the sensitivity of the cylinder pressure sensor, the control device determines that deposits are adhered to the cylinder pressure sensor.

Additional approaches for the reduction of particulate emissions in gasoline engines using optimized port+direct injection are described. These embodiments include control of the amount of directly injected fuel so as to avoid a threshold increase in particulates due to piston wetting and reduction of cold start emissions by use of air preheating using variable valve timing.

An electronic engine timing system that includes at least (1) an engine position sensor that includes a diametric magnet and two or more hall effect sensors configured and positioned to sense diametric magnet position, (2) sensor data receiving circuitry configured for receiving sensory input, including at least input from the engine position sensor; and (3) control circuitry configured to control firing of one or more cylinders of the engine at least in part by calculating one or more timing advance positions for one or more cylinders of the engine and by causing the one or more cylinders to fire according to the one or more calculated timing advance positions, the control circuitry further configured to calculate the one or more timing advance positions for the one or more cylinders separately from one another based at least in part on input from the engine position sensor.

To provide a controller and a control method, for an internal combustion engine, that can detect occurrence of knocking appropriately, even though the frequency distribution of the knock signal is distorted according to the occurrence state of knocking. The controller for the internal combustion engine calculates the background level by processing a low pass filter to the knock signal; and performs a low side frequency increase which makes a low side frequency, which is a cutoff frequency of the low pass filter in the case where the knock signal is smaller than an output value of the low pass filter, higher than a high side frequency, which is a cutoff frequency of the low pass filter in the case where the knock signal is larger than the output value of the low pass filter.

A system and method for assessing the presence or absence of ignition coil degradation for an ignition system that includes two ignition coils for each spark plug. Ignition coil degradation may be determined without having to monitor ignition coils via specialized hardware circuitry. In one example, degradation of one or more ignition coils may be inferred from cylinder the presence or absence of cylinder misfire.

A method for checking the association of structure-borne noise sensors of an internal combustion engine having a plurality of cylinders, which internal combustion engine can be operated in diesel operation or with individualized gas injection and in the case of which internal combustion engine a structure-borne noise sensor is arranged in the region of each cylinder, wherein the output signals of the structure-borne noise sensors reflect a knock index and are captured by a computing unit, wherein the internal combustion engine is operated in order to perform the method. The output signals of all structure-borne noise sensors are determined during at least one working cycle, which is formed by two revolutions of a crankshaft, in the respective positions of the crankshaft. The output signal of a cylinder is compared with the average value or the median value of the output signals of other cylinders.

The invention relates to a method for operating an internal combustion engine (1) provided with at least one working cylinder (3a-3d) each with an associated auxiliary cylinder (5a-5d), which engine (1) is operable in spark ignition and compression ignition modes. Each working cylinder (3a-3d) comprises a working piston (7a-7a) connected to a first crankshaft (9), and each auxiliary cylinder (5a-5d) comprises an auxiliary piston (10a-10d) connected to a second crankshaft (12). The first crankshaft (9) is connected to the second crankshaft (12) to drive the second crankshaft (12) at half the rotational speed of the first crankshaft (9). A device for controlling the phase angle is arranged between the first and second crankshafts. The method involves controlling the phase shift device in order to retain residual exhaust gas and increase the compression ratio. A current combustion phasing timing is determined, and the combustion phasing timing is corrected by increasing or decreasing the phase angle to achieve a desired combustion phasing timing.

An internal combustion engine knock determining device includes a vibration detector that produces a signal corresponding to engine vibration, an intensity computing unit that retrieves vibrational components in a plurality of frequency regions in which vibration intensity peaks are located when knock occurs, a background-noise computing unit that calculates background noise caused by factors other than knock, a frequency computing unit that determines specific frequency regions from which to determine whether knock is occurring by excluding certain frequency regions designated as frequency regions requiring exclusion due to the intensity of false-detection causing noise as a proportion of the background noise in the certain regions, and a knock determining unit that determines the occurrence of knock based on the vibration intensity in the specific frequency regions obtained by excluding the frequency regions requiring exclusion, wherein the number of specific frequency regions is increased to improve the accuracy of knock detection.

Fuel in a fuel tank is supplied by a low-pressure pump to intake passage injectors mounted on an intake manifold via a low-pressure fuel supply pipe and a low-pressure fuel distribution pipe. A high-pressure pump is provided on the low-pressure fuel supply pipe. The pressure of the fuel is boosted by the high-pressure pump, and then is supplied to in-cylinder injectors via a high-pressure fuel distribution pipe. In an intake passage injection (MPI) mode, excitation of a solenoid is stopped and operation of an electromagnetic spill valve is stopped so as reduce vibration and noise caused by the seating of the electromagnetic spill valve in a valve seat.

In one embodiment, a method of determining correct engine phase in an internal combustion engine without a cam sensor, the engine having a plurality of piston-cylinders that cause rotation of a crankshaft and a fuel delivery assembly associated with each of the plurality of piston-cylinders, the method comprising monitoring an engine parameter, modifying an amount of fuel delivered to a known piston-cylinder, advancing a spark time one of the plurality of piston-cylinders, and determining an actual engine phase based on a change in the engine parameter.