A method to determine the mass of air trapped in each cylinder of an internal combustion engine, which comprises determining, based on a model using measured and/or estimated physical quantities, a value for a first group of reference quantities; determining, based on the model, the actual inner volume of each cylinder as a function of the speed of rotation of the internal combustion engine and of the closing delay angle of the intake valve; and calculating the mass of air trapped in each cylinder as a function of the first group of reference quantities and of the actual inner volume of each cylinder.

A method is disclosed for controlling a compression release brake mechanism in a combustion engine. The method comprises: determining a desired exhaust manifold gas pressure level; continuously monitoring a set of control parameters, including at least two of cylinder pressure, exhaust manifold pressure, turbine speed and turbine expansion ratio; controlling a brake pressure valve and a variable turbine geometry by said control parameters, to drive one of the control parameters to a set first maximum level; and, while maintaining the first of the set of control parameters at the set first maximum level, controlling an exhaust gas recirculation valve by said control parameters in a closed loop to allow exhaust gas to recirculate towards an air inlet system while driving a second of the set of control parameters to a set second maximum level.

A misfire detection device and a misfire detection method for an internal combustion engine, and a memory medium are provided. Cylinders adjacent to the deactivated cylinder include a determined cylinder subject to a determination of whether a misfire has occurred and a cylinder different from the determined cylinder. It is determined that a misfire has occurred in the determined cylinder on condition that a divergence degree between a value of a combustion variable of the cylinder different from the determined cylinder and adjacent to the deactivated cylinder and a value of a combustion variable of the determined cylinder is greater than or equal to a specific amount. Combustion control has been executed in the cylinders adjacent to the deactivated cylinder and the cylinder different from the determined cylinder and adjacent to the deactivated cylinder.

A method of monitoring the usage of an internal combustion engine comprises performing an engine monitoring routine using a local monitoring device attached to an internal combustion engine. The engine monitoring routine includes generating data representative of a plurality of vibrations of an internal combustion engine using a vibration sensor of the local monitoring device, processing the generated data to determine a first value representative of a firing frequency of the internal combustion engine, generating an aggregated summary based on the first value and transmitting the aggregated summary and identification data for the local monitoring device to a remote application. The remote application processes the transmitted aggregated summary based on the identification data to determine engine speed usage data.

An engine control apparatus includes an ignition control section and an injection control section. When the partial compression ignition combustion is carried out, the ignition control section causes an ignition plug to carry out: main ignition in which a spark is generated in a late period of a compression stroke or an initial period of a expansion stroke to initiate the SI combustion; and preceding ignition in which the spark is generated at earlier timing than the main ignition. Also, when the partial compression ignition combustion is carried out, the injection control section causes the injector to inject fuel at such timing that the fuel exists in a cylinder at an earlier time point than the preceding ignition. The energy of the preceding ignition is set to be higher when the in-cylinder pressure specified by the in-cylinder pressure specification section is high than when the in-cylinder pressure is low.

An abnormality determination device of an internal combustion engine in which a breather line connects an intake-air path positioned upstream from a forced-induction system and a crankcase includes an intake-air flow rate sensor that detects an intake air flow rate in the intake-air path, a pressure sensor that detects a pressure of the breather line, and an abnormality determination unit that determines abnormality of the breather line. The abnormality determination unit estimates an intake air resistance of the intake-air path from the pressure when the engine is under low load conditions under which the intake air flow rate is less than a predetermined value and the pressure when the engine is under high load conditions under which the intake air flow rate is the predetermined value or greater and determines abnormality of the breather line when the intake air resistance is less than a threshold.

A method for operating the two stroke engine provides that the fuel valve is controlled after the starting process in at least a quasi-steady state such that, on the basis of uninterruptedly successive blocks of successive revolutions of the crankshaft, the fuel valve is opened and closed exactly once within each block. Each block includes from two to twenty revolutions of the crankshaft. The fuel valve is opened over a crankshaft angle (α) of more than 360° within one block in at least one operating state. A control device is provided for controlling the fuel valve. A quasi-steady state of the two stroke engine is a state in which the throttle element is adjusted by less than 10% of the maximum adjustment of the throttle element over a crankshaft angle (α) of 360°.

A synchronous dynamometer assembly for applying a load to an engine during at least one portion of the combustion cycle of the engine in a synchronised manner so as to be repeatable each cycle of the engine comprises a dynamometer having a non-inductive load which is applied to the engine during operation to vary the speed of the engine. The non-inductive load is variable by varying the current delivered to it. Crankshaft monitoring means monitors the rotational position of the engine crankshaft, and combustion detection means detects a combustion event in a cylinder of the engine. Control means is operatively connected to the dynamometer for applying the load from the dynamometer to the engine for at least one part of the combustion cycle in real time such that the different loads may be applied to the engine for different parts of the combustion cycle.

A method for evaluating the compression of the cylinders of an internal combustion engine of a vehicle having an electric starter motor and a respective starting battery, comprising: start capturing the battery voltage signal when the starter motor stars to rotate the internal-combustion engine so as to initiate operation of the engine under its own power; cease capturing the battery voltage signal when the engine enters operation under its own power; process the captured voltage signal for the location of local minimums; calculate the time difference between consecutive local minimums; detect if there is a variation of time between the calculated differences higher than a predetermined threshold between any said calculated time differences; and, if there is such variation, signal a potential engine malfunction. Also provided is a device for accomplishing the foregoing.

Systems and methods for estimating an engine event location are disclosed herein. In one embodiment, a control system is configured to receive feedback from at least one vibration sensor coupled to a reciprocating engine, estimate an engine parameter based at least on the feedback and an Empirical Transform Function (ETF), estimate a location of an engine event based on the engine parameter, and adjust operation of the reciprocating engine based at least on the location of the engine event.