Systems and methods for controlling and diagnosing air flow through a compressor without recirculating air flow through the compressor are presented. In one example, a position of an air flow control device located within a compressor housing is adjusted responsive to a request to diagnose flow through the compressor. The diagnostic may be performed while maintaining engine torque and speed.

Methods and systems are provided for operating a split exhaust engine system that provides blowthrough air and exhaust gas recirculation to an intake passage via a first exhaust manifold and exhaust gas to an exhaust passage via a second exhaust manifold. In one example, each of a first valve positioned in an exhaust gas recirculation (EGR) passage, the EGR passage coupled between the intake passage and the first exhaust manifold coupled to a first set of cylinder exhaust valves, and a second valve positioned in a flow passage coupled between the first exhaust manifold and the exhaust passage may be adjusted based on a measured pressure in the first exhaust manifold.

Methods and systems are provided for operating a split exhaust engine system that provides blowthrough air and exhaust gas recirculation to an intake passage via a first exhaust manifold and exhaust gas to an exhaust passage via a second exhaust manifold. In one example, each of a first valve positioned in an exhaust gas recirculation (EGR) passage, the EGR passage coupled between the intake passage and the first exhaust manifold coupled to a first set of cylinder exhaust valves, and a second valve positioned in a flow passage coupled between the first exhaust manifold and the exhaust passage may be adjusted based on a measured pressure in the first exhaust manifold.

An engine and a method of controlling the engine may include an EGR injector provided such that EGR gas sprays that are injected toward a side wall of a combustion chamber reach the side wall of a combustion chamber, simultaneously; an EGR pipe connecting the EGR injector to an exhaust system of the engine and ejecting exhaust gas from the exhaust system; an EGR pump mounted in the EGR pipe and pumping the exhaust gas in the EGR pipe to supply the exhaust gas to the EGR injector; and controller connected to the EGR pump and the EGR injector and configured for controlling the EGR pump and the EGR injector so that the EGR injector injects EGR gas into the combustion chamber.

An EGR gas distributor includes an inflow portion into which EGR gas that has passed through an EGR valve flows, a first EGR port connected to a section of the intake manifold in which intake air introduced into the first cylinder flows, a second EGR port connected to a section of the intake manifold in which intake air introduced into the second cylinder flows, a first gas passage that connects the inflow portion and the first EGR port to each other, and a second gas passage that connects the first gas passage and the second EGR port to each other. A shortest path between the first EGR port and the second EGR port is longer than both of a shortest path between the inflow portion and the first EGR port and a shortest path between the inflow portion and the second EGR port.

An intake system of a vehicle includes: an intake manifold having a plurality of runners for supplying intake gas to a multiple-cylinder engine; a surge tank cover coupled to the intake manifold to define a surge tank communicating with the plurality of runners via the intake manifold; an intake air inlet formed on the intake manifold as a passage through which intake air flows into the surge tank; an intake outlet formed on the intake manifold as a passage through which intake air sequentially passing through the intake air inlet, the surge tank, and the plurality of runners, and is discharged to the engine as the intake gas; a gas inlet which is a passage formed on the intake manifold and selectively receiving recirculation exhaust gas; and a gas chamber formed on the intake manifold so that the recirculation exhaust gas flows in through the gas inlet.

An intake system of a vehicle includes: an intake manifold having a plurality of runners for supplying intake gas to a multiple-cylinder engine; a surge tank cover coupled to the intake manifold to define a surge tank communicating with the plurality of runners via the intake manifold; an intake air inlet formed on the intake manifold as a passage through which intake air flows into the surge tank; an intake outlet formed on the intake manifold as a passage through which intake air sequentially passing through the intake air inlet, the surge tank, and the plurality of runners, and is discharged to the engine as the intake gas; a gas inlet which is a passage formed on the intake manifold and selectively receiving recirculation exhaust gas; and a gas chamber formed on the intake manifold so that the recirculation exhaust gas flows in through the gas inlet.

An engine and a method of controlling the engine may include an EGR injector provided such that EGR gas sprays that are injected toward a side wall of a combustion chamber reach the side wall of a combustion chamber, simultaneously; an EGR pipe connecting the EGR injector to an exhaust system of the engine and ejecting exhaust gas from the exhaust system; an EGR pump mounted in the EGR pipe and pumping the exhaust gas in the EGR pipe to supply the exhaust gas to the EGR injector; and controller connected to the EGR pump and the EGR injector and configured for controlling the EGR pump and the EGR injector so that the EGR injector injects EGR gas into the combustion chamber.

Methods and systems are provided for operating a split exhaust engine system that provides blowthrough air and exhaust gas recirculation to an intake passage via a first exhaust manifold and exhaust gas to an exhaust passage via a second exhaust manifold. In one example, an amount of opening overlap between a plurality of intake valves and a first set of exhaust valves coupled to the first exhaust manifold may be adjusted responsive to a transition from an estimated combustion air-fuel content to a leaner air-fuel content of the blowthrough air on a cylinder to cylinder basis. As one example, the transition may be determined from an output of an oxygen sensor positioned within the first exhaust manifold or an exhaust runner of each of the first set of exhaust valves.

Methods and systems are provided for operating a split exhaust engine system that provides blowthrough air and exhaust gas recirculation to an intake passage via a first exhaust manifold and exhaust gas to an exhaust passage via a second exhaust manifold. In one example, an amount of opening overlap between a plurality of intake valves and a first set of exhaust valves coupled to the first exhaust manifold may be adjusted responsive to a transition from an estimated combustion air-fuel content to a leaner air-fuel content of the blowthrough air on a cylinder to cylinder basis. As one example, the transition may be determined from an output of an oxygen sensor positioned within the first exhaust manifold or an exhaust runner of each of the first set of exhaust valves.