A control apparatus of an internal combustion engine having an injector which directly injects fuel into a combustion chamber of a cylinder and a spark plug which ignites an air-fuel mixture containing the fuel injected by the injector includes an air-fuel ratio acquisition unit acquiring an air-fuel ratio of the air-fuel mixture in the combustion chamber, a nitrogen oxide concentration acquisition unit acquiring a concentration of nitrogen oxide in a combustion gas exhausted from the internal combustion engine, and a stratification level estimation unit estimating a level of stratification as a measure of level of distribution of the air-fuel mixture at a predetermined air-fuel ratio or below in a vicinity of the spark plug. The stratification level estimation unit estimates the level of stratification according to the air-fuel ratio acquired by the air-fuel ratio acquisition unit and the concentration of nitrogen oxide acquired by the nitrogen oxide concentration acquisition unit.

The invention concerns a method (200) for operating a motor vehicle (100) with a combustion engine (110), including the determination (210) of a current operating state of the vehicle (100), the determination (220) of an emission state of the vehicle (100) during the determined operating state, carrying out (230) at least one measure to reduce emissions depending on the emission state and evaluating (240) the at least one measure in connection with the operating state with regard to its success in reducing emissions. Furthermore, a computing unit (130) and a computer program product for carrying out such a method (200) are proposed.

A powertrain control unit may be configured to control an engine and identify a first operating condition is expected to fulfill a demand for output with an exhaust stream having a first amount of a pollutant (e.g., NOx, particulate matter), and a second operating condition expected to fulfill the demand with an exhaust stream having a reduced amount of the pollutant as compared to the first amount. The powertrain control unit may receive duty cycle information to control the engine to fulfill the demand per the second operating condition, yielding the reduced amount of pollutant in the exhaust. Duty cycle information may include speed, location, position, rotation, temperature, and/or other information. A vehicle, backhoe, bulldozer, crane, and/or combine harvester may comprise the powertrain control unit and an engine and aftertreatment system. An exhaust aftertreatment system may be remotely activated, which may reduce warmup time associated with emissions mitigation.

The disclosure relates to a self-adaptive oil spraying control system and method for a biodiesel engine. The control system includes an exhaust pipe, a gas sensor, a control module and an oil sprayer, wherein the exhaust pipe is connected to the oil sprayer, the gas sensor is mounted in the exhaust pipe, and the gas sensor and the oil sprayer are connected to the control module respectively. According to the control method, a main spray advance angle of the engine is subjected to closed-loop control directly through comparison between an idling steady state NO.sub.x emission signal and an idling steady state NO.sub.x emission value of pure diesel when the engine uses the biodiesel, so that emission of NO.sub.x in the exhaust is reduced. Compared with the prior art, the disclosure has the advantages of no need of detecting a biodiesel ratio, high efficiency, good effect and the like.

The present disclosure relates to improvements in turbocharger efficiency and more particularly to a method and system for estimating the efficiency loss of a turbocharger. The method comprises the steps of monitoring a plurality of operating parameters and determining a compressor exit temperature according to a first calibration map based on these operating parameters. An estimate of instantaneous turbocharger efficiency loss according to a second calibration map is then determined, based on the compressor exit temperature. The instantaneous turbocharger efficiency loss is used to determine an estimate of cumulative turbocharger efficiency loss during engine service. The estimate of cumulative turbocharger efficiency loss is compared with a first predetermined efficiency loss threshold and a first signal is generated if the first predetermined efficiency loss threshold is exceeded.

A method includes: initiating a low engine-out NOx (LEON) mode by controlling a component of a vehicle having an aftertreatment system to decrease an instantaneous engine-out NOx (EONOx) amount; comparing a temperature of the aftertreatment system during the LEON mode to a warm-operation threshold temperature; responsive to determining that the temperature of the aftertreatment system exceeds the warm-operation threshold temperature, disengaging the LEON mode; responsive to determining that the temperature of the aftertreatment system is below the warm-up operation threshold temperature, comparing information indicative of an operating status of the vehicle to a LEON exit threshold; and disengaging the LEON mode responsive to determining that the information indicative of the operating status of the vehicle during the LEON mode exceeds the LEON exit threshold.

Method for diagnosing at least one exhaust gas sensor (22;24;26) of an internal combustion engine (10) disposed in an exhaust duct (21), where ambient air (12) is actively introduced into the exhaust duct (21) by means of a device (27), when an operating state is present in which the internal combustion engine (10) does not produce an exhaust gas mass flow, and the diagnosis of the at least one exhaust gas sensor (22;24;26) disposed in the exhaust duct (21) is subsequently carried out.

A system and method of integrating an engine having dynamic skip fire control with an exhaust gas recirculation system in a turbocharged internal combustion engine is described. An engine control system determines an appropriate firing pattern based at least in part on a desired exhaust gas recirculation flow rate. Signals from sensors in the intake manifold and exhaust system may also be used as part of a feedback loop to determine a desired exhaust gas recirculation flow rate.

Methods and systems for monitoring a NOx sensor for a NOx offset value are described. In one example, the NOx offset value may be based on a minimum NOx concentration observed over an entire drive of a vehicle. The NOx offset monitor may be inhibited in response to inferring or detecting a presence of NH.sub.3 in an exhaust system.

The present disclosure relates to a gas engine heat pump including: an engine which burns a mixed air of air and fuel; a first charger which compresses the mixed air and supplies to the engine; a first exhaust flow path which is connected to the engine, and through which exhaust gas discharged from the engine flows; and a second charger which is driven by the exhaust gas branched from the first exhaust flow path to a second exhaust flow path, and compresses the exhaust gas discharged from the engine and supplies the compressed exhaust gas to the engine, thereby reducing the emission of nitrogen oxide by recirculating the exhaust gas without additional power consumption.