49results about How to "Deterioration in fuel economy" patented technology

In a motor vehicle of the invention, when an intake air temperature Ta is not lower than a preset reference temperature Tref, warm-up drive control selectively uses an evaporated fuel processing acceleration operation curve, which gives a high level of a negative pressure in an intake manifold, to set a target drive point of an engine and controls the operation of the engine. This ensures good emission of the engine. When the intake air temperature Ta is lower than the preset reference temperature Tref and when the setting of a heating demand Hq requires heating, on the other hand, the warm-up drive control increases an EGR quantity from an ordinary level and switches over an operation mode of a cooling system for the engine to a warm-up circulation mode for making the flow of a cooling medium bypass a radiator. This introduces a greater amount of heat of exhaust into a heat exchanger to enable quick supply of the warm air to a passenger compartment. The warm-up drive control selectively uses a negative pressure reduction operation curve, which gives a lower level of the negative pressure in the intake manifold than the level of the negative pressure set on the evaporated fuel processing acceleration operation curve, to set the target drive point of the engine and controls the operation of the engine. This enhances the operation efficiency of the engine and improves the fuel economy during the warm-up time of the engine.

The internal combustion engine control apparatus of the invention starts gradually delaying an ignition timing θ for catalyst warm-up, immediately after a start of an internal combustion engine. When the ignition timing θ is delayed to or below a preset reference timing θref, a fuel amount increase flag F1 is set to 1 to start increase correction of a fuel injection amount. The internal combustion engine control apparatus then starts gradually increasing a throttle opening TH to a preset target opening THset. The increase correction of the fuel injection amount is terminated after elapse of a preset time t3 since the increase of the throttle opening TH to the preset target opening THset. This arrangement enables the increase correction of the fuel injection amount according to the requirement, thus improving the fuel economy and the emission.

In a control apparatus for an internal combustion engine, The ignition timing in a rich-cylinder is corrected toward a retardation side from a theoretical-MBT such that the torque generated in the rich-cylinder exceeds a torque generated in the rich-cylinder at the theoretical-MBT, and the ignition timing in a lean-cylinder is corrected toward an advancement side from the theoretical-MBT such that the torque generated in the lean-cylinder exceeds a torque generated in the lean-cylinder at the theoretical-MBT, when a temperature raising process is being executed, and the ignition timing in the rich-cylinder is corrected further toward the retardation side such that the torque generated in the rich-cylinder becomes equal to or smaller than a maximum theoretical generated torque and equal to or larger than the torque generated in the lean-cylinder at the theoretical-MBT, when the temperature raising process is being executed and the engine is in a low-load operating state.

An automatic transmission includes a first planetary gear set; a second planetary gear set; a third planetary gear set; an input shaft; an output shaft; and five friction elements. A first ring gear is constantly locked. A third sun gear is connected with a first sun gear to define a first rotating member, and a second sun gear is connected with a first carrier to define a second rotating member. The input shaft is constantly connected with the first rotating member, and the output shaft is constantly connected with a third carrier. The five friction elements include a first friction element adapted to selectively connect a second ring gear with a third ring gear, a second friction element adapted to stop a rotation of a second carrier, a third friction element adapted to selectively connect the second carrier with the third ring gear, a fourth friction element adapted to selectively connect the second ring gear with the third carrier, and a fifth friction element adapted to selectively connect the first rotating member with the second carrier. Each of at least seven forward speed-ratios and one reverse speed-ratio is achieved by an engaged state of two friction elements selected from the five friction elements.