摘要:
A method and system for controlling output torque of an internal combustion engine during a gearshift in an automatic shift manual transmission coupled to the engine is disclosed. The transmission includes a multiplicity of gears and a clutch actuated by a transmission control unit (TCU), which controls clutch disengagement, gear change, and clutch re-engagement. The engine includes an engine control unit in communication with the TCU. The method includes determining engine operator demanded engine torque; sending a signal to the engine control unit in response to actuation of the clutch; and, computing in the engine control unit in response to the sent clutch actuation signal and the determined engine operator demanded engine torque, a control signal for the engine, such engine, in response to such control signal changing engine torque during the gear change to substantially match demanded engine torque when the clutch is re-engaged.
摘要:
A system (12) and method for determining the closed position of a throttle plate 52 of an internal combustion engine (10) are provided. The system (12) includes a throttle sensor (56), a temperature sensor (70 or 86), and an electronic control unit (ECU) (72). The throttle sensor (56) generates a signal indicative of the position of the throttle plate (52). The temperature sensor (70 or 86) generates a signal indicative of the temperature of a throttle body (50) of the engine (10). The ECU (72) is configured to select one of a first closed position value indicated by throttle sensor (56) signal and a second closed position value retrieved from a memory (94) responsive to the measured temperature. The inventive system is able to minimize inaccuracies in throttle plate position detection by eliminating errors resulting from a change in geometry between the throttle plate (52) and the throttle body (50) of the engine during relatively high temperatures.
摘要:
A closed throttle position of a vehicle internal combustion engine is determined by storing a plurality of signal values representative of previous foot-off position values of an accelerator pedal (10) within a normal range of pedal positions, determining a current foot-off position value of the accelerator pedal, comparing the current foot-off position value to an average of the previous stored foot-off position values, and using the average as the closed pedal position to determine a closed throttle position when the comparison is indicative of an abnormal pedal position.
摘要:
A method and system for controlling the operation of an internal combustion engine, wherein exhaust gas generated by the engine is directed through an emission control device, includes determining instantaneous rates of storage for a constituent of the exhaust gas, such as NOx, as well as the capacity reduction of the device to store the exhaust gas constituent as a function of a calculated value representing an amount of SOx which has accumulated in the device since a prior device-regeneration (desulfation) event. The calculated accumulated SOx value is also preferably used to schedule a device-regeneration event, as when the calculated accumulated SOx value exceeds a predetermined threshold value.
摘要:
As one example, a method of operating an engine system including a first air intake passage branch including a first compression device and a second air intake passage branch including a second compression device, wherein each of the first branch and the second branch are fluidly coupled to at least a combustion chamber the engine via a common intake passage, a first sensor arranged along the first branch and at least a second sensor arranged along the common intake passage, wherein the first sensor is a mass airflow sensor and wherein the second branch does not include a mass airflow sensor. The method comprises increasing the mass airflow through the first branch relative to the mass airflow through the second branch when an amount of decrease in the mass airflow through the first branch is more than half an amount of a corresponding decrease in the combined mass airflow.
摘要:
An exhaust treatment system for an internal combustion engine includes a catalytic emission control device. When transitioning the engine between a lean operating condition and a stoichiometric operating condition, as when scheduling a purge of the downstream device to thereby release an amount of a selected exhaust gas constituent, such as NOx, that has been stored in the downstream device during the lean operating condition, the air-fuel ratio of the air-fuel mixture supplied to each cylinder is sequentially stepped from an air-fuel ratio of at least about 18 to the stoichiometric air-fuel ratio. The purge event is preferably commenced when all but one cylinders has been stepped to stoichiometric operation, with the air-fuel mixture supplied to the last cylinder being stepped immediately to an air-fuel ratio rich of a stoichiometric air-fuel ratio.
摘要:
An exhaust gas treatment system for an internal combustion engine includes a three-way catalyst and a NOx device located downstream of the three-way catalyst. The device is preconditioned for emissions reduction at engine operating conditions about stoichiometry by substantially filling the device with oxygen and NOx; and purging stored oxygen and stored NOx from only an upstream portion of the device, whereupon the upstream portion of the device operates to store oxygen and NOx during subsequent lean transients while the downstream portion of the device operates to reduce excess HC and CO during subsequent rich transients.
摘要:
An exhaust gas treatment system for an internal combustion engine includes a pair of upstream emission control devices which respectively receive the exhaust gas generated by a respective group of cylinders, and a single, shared downstream emission control device receiving catalyzed exhaust gas from each of the upstream emission control devices. After the downstream device stores a selected constituent gas generated when each cylinder group is operating “lean,” the downstream device is purged by operating the first cylinder group with a stoichiometric air-fuel mixture while operating the second cylinder group with a rich air-fuel mixture, such that the combined catalyzed exhaust gas flowing through the downstream device during the purge event has an air-fuel ratio slightly rich of stoichiometry. As a result, the invention improves overall vehicle fuel economy because only one of the upstream devices is purged of stored oxygen when purging the downstream device of previously-stored constituent gas.
摘要:
A nitrous oxide trap temperature control system for desulfating the trap uses and engine with some cylinders operating with lean combustion and some cylinders operating with rich combustion. The lean and rich combustion gases are combined to form an mixture which is fed to the trap to provide an exothermic reaction. The desired lean and rich air/fuel ratios of the respective lean and rich cylinders are limited depending on trap temperature and incremental heat addition to prevent inadvertently decreasing trap temperature.
摘要:
An engine control computer estimates the cumulative NO.sub.x storage in a NO.sub.x trap based on engine operating conditions and enters a NO.sub.x purge mode of operation when a maximum storage capacity limit, based on trap temperature, is exceeded. The purge mode is terminated when NO.sub.x storage level decreases below a minimum storage capacity limit. The rate of NO.sub.x dissipation is also based on trap temperature.