A system and method including one or more conduits, a pump system, and a controller. The conduits are fluidly coupled with a cooling device that is operably coupled with an engine to cool at least a portion of exhaust from the engine. The pump system pumps a cleaning fluid from a cleaning fluid source through the one or more conduits and into a flow path of a portion of the exhaust from the engine while the engine continues to operate. The controller monitors operation of the engine and determines whether the engine is operating in a designated state. The controller controls the pump system to pump the cleaning fluid into the flow path of a portion the exhaust from the engine to clean the cooling device while the engine operates in the designated state and the exhaust flows from the engine and through the cooling device.

An engine unit includes an engine, an exhaust gas recirculation device including a communication pipe by which an exhaust pipe of the engine and an intake pipe of the engine to communicating and a valve that is provided in the communication pipe, and a control device. The control device is configured to perform a foreign matter removal control that is opening and closing the valve when catching of foreign matter in the valve is detected and the engine stops.

An engine unit includes an engine, an exhaust gas recirculation device including a communication pipe by which an exhaust pipe of the engine and an intake pipe of the engine to communicating and a valve that is provided in the communication pipe, and a control device. The control device is configured to perform a foreign matter removal control that is opening and closing the valve when catching of foreign matter in the valve is detected and the engine stops.

A hybrid vehicle includes an engine, an exhaust gas recirculation device, a traveling motor, and a control device. The exhaust gas recirculation device includes a communication pipe that allows an exhaust pipe and an intake pipe of the engine to communicate with each other and a valve that is provided in the communication pipe. The control device is configured to perform foreign matter removal control for opening and closing the valve when foreign matter caught in the valve is detected and the hybrid vehicle stops.

A hybrid vehicle includes an engine, an exhaust gas recirculation device, a traveling motor, and a control device. The exhaust gas recirculation device includes a communication pipe that allows an exhaust pipe and an intake pipe of the engine to communicate with each other and a valve that is provided in the communication pipe. The control device is configured to perform foreign matter removal control for opening and closing the valve when foreign matter caught in the valve is detected and the hybrid vehicle stops.

An engine system includes a throttle device, an EGR valve, and an ECU. The ECU diagnoses foreign-matter lodging abnormality of the EGR valve and the foreign-matter diameter based on intake pressure. When the existence of the abnormality and the foreign-matter diameter are determined, the ECU calculates a difference between a foreign-matter diameter and a predetermined learning determination value as a foreign-matter diameter difference. If this difference is larger than an abnormality determination value, the foreign-matter diameter is judged to be excessive and the throttle device is controlled to avoid engine stall. If the foreign-matter diameter difference is equal to or larger than a normality determination value and also equal to or less than the abnormality determination value, engine deceleration is continued. If the foreign-matter diameter difference is less than the normality determination value, the foreign-matter diameter is judged to be minute and the learning determination value is updated.

An engine control device controls an engine. The control device includes a controller. The controller is configured to open the air bypass valve of the engine and close the waste gate valve of the engine when a first condition is satisfied, and thereafter determine that an execution condition of a boost pressure increase control is satisfied when a second condition is satisfied. The air-bypass valve disposed on an air-bypass passage that communicates between an upstream side and a downstream side of a compressor in an intake passage. The waste gate valve disposed on a waste gate passage that communicates between an upstream side and a downstream side of the turbine in an exhaust passage. The first condition represents a turbine pre-rotation start request, and the second condition represents a boost pressure increase request.

An engine control device controls an engine. The control device includes a controller. The controller is configured to open the air bypass valve of the engine and close the waste gate valve of the engine when a first condition is satisfied, and thereafter determine that an execution condition of a boost pressure increase control is satisfied when a second condition is satisfied. The air-bypass valve disposed on an air-bypass passage that communicates between an upstream side and a downstream side of a compressor in an intake passage. The waste gate valve disposed on a waste gate passage that communicates between an upstream side and a downstream side of the turbine in an exhaust passage. The first condition represents a turbine pre-rotation start request, and the second condition represents a boost pressure increase request.

An EGR device includes an EGR flow path, an EGR valve, a stepping motor, a motor driver, a return spring, a speed detector, and an opening degree estimator. The EGR flow path conveys exhaust gas from an exhaust flow path of an engine to an intake flow path. The EGR valve is disposed on the EGR flow path. The stepping motor drives the EGR valve to open to close. The motor driver supplies driving power to the stepping motor. The return spring urges the EGR valve in a valve closing direction. The speed detector detects an output shaft rotation speed of the engine. The opening degree estimator estimates an opening degree of the EGR valve. The motor driver changes a drive frequency of the stepping motor according to variations of the output shaft rotation speed detected by the speed detector and the opening degree estimated by the opening degree estimator.

An exhaust gas recirculation valve warming device includes an exhaust throttle arranged in an exhaust passage, an exhaust gas recirculation passage that extends from a portion of the exhaust passage that is upstream of the exhaust throttle and is connected to an intake passage, an exhaust gas recirculation valve arranged in the exhaust gas recirculation passage, and a branch passage that extends from a portion of the exhaust gas recirculation passage that is upstream of the exhaust gas recirculation valve in a direction in which exhaust gas flows, in which the branch passage is connected to a portion of the exhaust passage that is downstream of the exhaust throttle. The exhaust gas recirculation valve includes a valve passage that forms part of the exhaust gas recirculation passage and a warming passage that forms part of the branch passage.