Abstract: An internal combustion engine to which a controller is applied includes a cylinder, a turbocharger, an intake passage, a throttle valve, and an exhaust passage. The turbocharger includes a turbine wheel, a compressor wheel, and a wastegate valve. The controller executes a loss estimating process that calculates an estimated value of a pumping loss of the internal combustion engine from an intake air pressure, which is air pressure at a downstream side of the throttle valve in the intake passage, an engine speed of the internal combustion engine, and a charging pressure.

Abstract: A control apparatus for an internal combustion engine, the internal combustion engine including a plurality of cylinders, and the control apparatus including: an electronic control unit configured to: a) determine whether or not acceleration of a crank shaft at compression top dead center is equal to or greater than a threshold value; b) determine that a compression loss has occurred in the cylinder, when the acceleration of the crank shaft is equal to or greater than the threshold value; and c) prohibit the determination of compression loss, when acceleration of rotation of the crank shaft at compression top dead center has occurred a first specific number of times consecutively in the plurality of cylinders.

Abstract: In a method and a device for operating an internal combustion engine, with at least one cylinder (Z1-Z4) having a combustion chamber (26), fuel is injected into the cylinder and a logic value (LV_FCUT) is set, in particular for stopping the injection of fuel into the cylinder, The method furthermore has the following steps: depending on a course of the highly time-resolved measurement signal of a rotational speed (N_FAST) of the internal combustion engine, a local maximum value (N_FAST_MAX) of the rotational speed is determined, a rotational speed difference (N_FAST_DIF) between the local maximum value (N_FAST_MAX) and a current measured value (N_FAST_MES) of the rotational speed is determined, and, depending on the determined rotational speed difference (N_FAST_DIF), the logic value (LV_FCUT) is set.

Abstract: An inter-cylinder air-fuel ratio variation abnormality detection apparatus is disclosed. The apparatus determines imbalance of an air-fuel ratio among the cylinders based on a difference between index values correlated with crank angular velocities detected in a set of opposite cylinders belonging to different banks and having crank angles different from one another by 360°; and carries out an air-fuel ratio feedback process for controlling an amount of injected fuel for each of the banks, wherein the apparatus comprises a correction unit correcting, before determining the air-fuel ratio imbalance, the difference between the index values in a direction of combustion improvement for opposite cylinders that are opposite to cylinders belonging to a bank identical to a bank of a cylinder with the most deviating index value from a standard value among all the cylinders and being other than the cylinder with the most deviating index value.

Abstract: In a method for detecting a deviation of a compression pressure of one cylinder from that of another cylinder of an internal combustion engine having at least two cylinders, the rotational speed of a crankshaft of the internal combustion engine is reduced from a starting rotational speed to a target rotational speed; the actual rotational speed is detected; a curve of a change of the actual rotational speed per angle unit of the crankshaft is determined as a curve of a rotational speed gradient; the curve of the rotational speed gradient is subjected to order analysis; and a deviation of the compression pressure of one cylinder from that of another cylinder is detected when an amplitude of a selected order lies above a permissible threshold value.

Abstract: An abnormality detection apparatus for a multi-cylinder internal combustion engine changes a fuel injection quantity of a predetermined target cylinder to detect an abnormality of an internal combustion engine based on values of rotational variations relating to the target cylinder detected before and after the change of the fuel injection quantity. The abnormality detection apparatus corrects the values of the rotational variations relating to the target cylinder detected before and after the change of the fuel injection quantity based on at least one of the number of revolutions of the engine and an engine load at a corresponding detection time.

Abstract: A reference signal generator generating a reference signal for high-resolution measurement/control in real time includes a means for calculating the rotational trend, e.g. increase/decrease in the r.p.m.

Abstract: A method for inferring Indicated Mean Effective Pressure as total transient indicated engine torque in an internal combustion engine, comprising the steps of acquiring at least one crankshaft time stamp for use in determining a cylinder-specific engine velocity; calculating an incremental change in engine kinetic energy from the previously fired cylinder (j?1st) to the currently fired (jth) cylinder using the cylinder-specific engine velocity; equating the incremental change in engine kinetic energy to a change in energy-averaged cylinder torque (IMEP) from the previously-fired (j?1st) to a currently-fired (jth) cylinder; summing a plurality of the incremental changes in engine kinetic energy over time to determine a value of the transient component of indicated torque; determining a value of the quasi-steady indicated engine torque; and adding the value of transient component of indicated torque to the value of quasi-steady indicated engine torque to yield the Indicated Mean Effective Pressure.