摘要:
Methods and systems are provided for a boosted engine having a split intake system coupled to a split exhaust system. Aircharges of differing composition, pressure, and temperature may be delivered to the engine through the split intake system at different points of an engine cycle. In this way, boost and EGR benefits may be extended.
摘要:
An embodiment of an engine is described. The engine includes a first throttle valve. The first throttle valve is provided in a first intake passage coupled to an intake manifold. The first throttle valve has a default closed position. The engine further includes a second throttle valve. The second throttle valve is provided in a second intake passage coupled to the intake manifold. The second throttle valve has a default open position. The engine further includes a venturi pump that is provided between the second throttle valve and the intake manifold. When the second throttle valve is in the default open position, intake air flows through the venturi pump.
摘要:
Method and systems are provided for controlling a vehicle system including an engine that is selectively deactivated during engine idle-stop conditions. One example method comprises, adjusting a brake torque applied to a deactivated rotating engine after an engine restart request, the brake torque applied to slow the engine to at least a predetermined threshold speed without stopping the engine, and engaging a starter to the still rotating engine to increase the engine speed and restart the engine.
摘要:
A system and method for supplying fuel to an engine is disclosed. In one example, a first controller supplies injector commands to a second controller via an asynchronous serial communication bus. The system may reduce the complexity of supplying two or more fuels to an engine.
摘要:
Systems and methods are provided for monitoring reverse flow of fuel vapors and/or air through a vehicle fuel vapor recovery system, the fuel vapor recovery system coupled to an engine intake of a boosted internal combustion engine. One example method comprises, intermittently adjusting a restriction in the fuel vapor recovery system during boosted conditions, and indicating degradation based on one or more of a change in a pressure value, or based on a change in flow in the fuel vapor recovery system.
摘要:
Methods and systems are provided for controlling a vehicle system including an engine that is selectively deactivated during engine idle-stop conditions and selectively reactivated during engine restart conditions. One example method comprises, during an engine restart from an idle stop, performing a first combustion event in a cylinder with a piston at an engine crankshaft position that is after a crankshaft position at which said cylinder's exhaust valve opens, and before a crankshaft position at which the cylinder's intake valve closes, during a cycle of said cylinder. In this way, inaccuracies in cylinder aircharge estimation may be reduced, thereby also reducing air-fuel ratio errors and improving the quality and repeatability of engine restarts.
摘要:
A method for operating an engine of a vehicle. During a warm-up period following a cold start of the vehicle, a cylinder of the engine is charged to a reduced air-charge pressure, and fuel is injected into the cylinder. After the warm-up period, the cylinder is charged to a non-reduced air-charge pressure, greater for an equivalent driver demand than the reduced air-charge pressure, and fuel is injected into the cylinder.
摘要:
A turbocharger compressor bypass valve is disclosed. In one example, the compressor bypass valve operates inversely proportional to engine throttle operation. The approach may simplify compressor bypass valve control and reduced engine system complexity.
摘要:
A selectively operable vacuum source is disclosed. In one example, vacuum source supplies as much air to an engine as is drawn by the vacuum source from a vacuum reservoir. The approach may provide vacuum to a vehicle vacuum system efficiently and with less weight than other vacuum sources.
摘要:
Methods and systems are provided for controlling a vehicle system including an engine that is selectively deactivated during engine idle-stop conditions. One example method includes, during a first condition, engaging an engine starter, without applying a starter current, to the deactivated rotating engine after the engine speed drops below a threshold speed. The method further includes, during a second condition, engaging the starter and adjusting a starter motor switch to apply a starter braking torque to the rotating engine.