Present embodiments provide a throttle body which may be used with a variety of engines of different manufacturers. The throttle body includes an inlet which expands to two or more bores, which extend downwardly through the throttle body. The throttle body may provide improved fuel pathways and fuel injector placement.

Methods and systems are provided for monitoring a NOx storage capacity of a passive NOx adsorption catalyst (PNA) included in an exhaust gas after-treatment system of an engine. In one example, a method may include, after an engine cold start and prior to an exhaust gas temperature reaching an upper threshold temperature, indicating degradation of the PNA based on an amount of NOx measured downstream of the PNA during a fuel cut event and while the exhaust gas temperature is between a lower threshold temperature and the upper threshold temperature. In this way, degradation of the NOx storage capacity may be inferred based on an amount of NOx released from the PNA and independent of a NOx storage measurement.

Methods and systems are provided for catalyst control. In one example, a method may modulate a downstream catalyst by applying a square waveform to an outer feedback control loop. A fuel adjustment is performed in accordance with the square waveform to create an air-fuel ratio oscillation at an upstream catalyst brick and at a downstream catalyst brick.

Methods and systems are provided for catalyst control. In one example, a method may modulate a downstream catalyst by applying a square waveform to an outer feedback control loop. A fuel adjustment is performed in accordance with the square waveform to create an air-fuel ratio oscillation at an upstream catalyst brick and at a downstream catalyst brick.

A control system for fuel injection by predicting engine noise may include an engine noise predicting device configured to derive a predicted engine noise value in real time by a predicted engine noise coefficient which is pre-stored according to a currently measured combustion pressure value of an engine; and a combustion controller configured to determine a difference between the real-time predicted engine noise value derived by the engine noise predicting device and a target engine noise value for a current operation condition of the engine, and when the engine noise is determined as being degraded due to an abnormal combustion, configured to change the target engine noise value to control fuel injection according to the changed target engine noise value.

A blow-by gas treating device discharges blow-by gas into intake air. A controller selects and executes one of a fuel cutoff process and a fuel introduction process when stopping combustion in a cylinder under a situation in which a crankshaft of the internal combustion engine is rotating. An injection valve controlling section controls a fuel injection valve to regulate a fuel injection amount in a period in which the combustion in the cylinder is stopped under the situation in which the crankshaft is rotating. The injection valve controlling section decreases the fuel injection amount from the fuel injection valve as an oil temperature that is the temperature of engine oil increases.

In a control system for an internal combustion engine, the internal combustion engine includes a first exhaust catalyst that is a three-way catalyst disposed in an exhaust path of the internal combustion engine, a second exhaust catalyst that is a three-way catalyst disposed in the exhaust path on a downstream side of the first exhaust catalyst, and a motor configured to drive the internal combustion engine. The control system includes an electronic control unit configured to, when operation of the internal combustion engine is stopped, stop fuel injection in the internal combustion engine and then, execute motoring in which the internal combustion engine is rotationally driven using drive power of the motor, and execute the motoring in a range in which an oxygen occlusion amount of the first exhaust catalyst becomes an oxygen occlusion amount smaller than an upper limit oxygen occlusion amount of the first exhaust catalyst.

A combination system may include a carburetor in fluid communication with an engine intake tract and a fuel injector in fluid communication with the engine intake tract.

A control process for controlling an engine speed governor of an engine is provided. The process comprises the steps of calculating the current engine power being developed by the engine, and determining an appropriate engine speed for the current engine power based upon a first engine map. The process then instructs the speed governor to adjust the engine speed in accordance with the first map if required. The process monitors for desired engine power requests, and calculates a power ratio of desired engine power versus current engine power upon receiving a desired engine power request. The process then establishes an engine speed adjustment value based upon a second engine map of power ratio versus speed adjustment value, and instructs the speed governor to adjust the engine speed in accordance with the speed adjustment value. A speed governor system incorporating the control process, and a work machine or vehicle incorporating such a system are also provided.

A control device for an internal combustion engine includes an electronic control unit. The electronic control unit is configured to control an injection amount and an injection timing of fuel to a target injection amount and a target injection timing set based on an engine operation state, detect an ignition timing of fuel based on a vibration component of an engine body in a specific frequency bandwidth, and correct at least one of the target injection amount and the target injection timing based on a deviation between the detected ignition timing and a target ignition timing according to the engine operation state. The specific frequency bandwidth is a bandwidth on a low frequency side of a frequency bandwidth where the engine body undergoes elastic vibration.