Methods and systems are provided for an EGR system reverse hose diagnostic. In one example, a method includes executing the reverse hose diagnostic in response to an EGR flowrate exceeding a threshold flow rate.

A method including: repeatedly obtaining information in a control unit regarding a set operation value and an actual operation value of a component, unit, or system; repeatedly evaluating a difference between a set operation value and the actual operation value; if a difference exceeds a predefined minimum difference, measuring a response time from when the minimum difference was exceeded until a predefined change of the actual value is achieved, and/or measuring a change of the actual value during a predefined response time, remaining active if the set operation value is continuously exceeds the actual value; and if the response time is longer than the predefined response time and/or if the change of the actual value has not achieved the predefined change, generating a fault signal.

A method including: repeatedly obtaining information in a control unit regarding a set operation value and an actual operation value of a component, unit, or system; repeatedly evaluating a difference between a set operation value and the actual operation value; if a difference exceeds a predefined minimum difference, measuring a response time from when the minimum difference was exceeded until a predefined change of the actual value is achieved, and/or measuring a change of the actual value during a predefined response time, remaining active if the set operation value is continuously exceeds the actual value; and if the response time is longer than the predefined response time and/or if the change of the actual value has not achieved the predefined change, generating a fault signal.

Proposed is a method and system for controlling an Exhaust Gas Recirculation (EGR) device in high-load driving, and an internal combustion engine vehicle including the system. The method of controlling an EGR device in high-load driving compares a ratio of pressures at a front end and a rear end of a throttle valve with a preset critical value that is a reference for determining high-load driving, performs Wide Open Throttle (WOT) control for fully opening the throttle valve when the ratio of pressures is larger than the preset critical value, determines whether engine torque due to the WOT control and use of EGR satisfies torque requested by a driver, and corrects throttle opening or stops use of EGR, depending on whether the engine torque due to use of EGR together with the WOT control satisfies the requested torque.

Proposed is a method and system for controlling an Exhaust Gas Recirculation (EGR) device in high-load driving, and an internal combustion engine vehicle including the system. The method of controlling an EGR device in high-load driving compares a ratio of pressures at a front end and a rear end of a throttle valve with a preset critical value that is a reference for determining high-load driving, performs Wide Open Throttle (WOT) control for fully opening the throttle valve when the ratio of pressures is larger than the preset critical value, determines whether engine torque due to the WOT control and use of EGR satisfies torque requested by a driver, and corrects throttle opening or stops use of EGR, depending on whether the engine torque due to use of EGR together with the WOT control satisfies the requested torque.

A method of operating exhaust gas recirculation pump for an internal combustion engine including: providing an EGR pump assembly including an electric motor coupled to a roots device having rotors, the EGR pump operably connected to an internal combustion engine; providing an EGR control unit linked to the EGR pump assembly; providing sensors linked to the EGR control unit; determining if a motor speed is within a predetermined target in step S1 wherein when motor speed=predetermined target then; determining if a motor torque is within a predetermined target in step S2 wherein when motor torque=predetermined target then; determining if a motor temperature is within a predetermined target in step S3 wherein when motor temperature=predetermined target then; and maintaining operation of the exhaust gas recirculation pump.

A method of operating exhaust gas recirculation pump for an internal combustion engine including: providing an EGR pump assembly including an electric motor coupled to a roots device having rotors, the EGR pump operably connected to an internal combustion engine; providing an EGR control unit linked to the EGR pump assembly; providing sensors linked to the EGR control unit; determining if a motor speed is within a predetermined target in step S1 wherein when motor speed=predetermined target then; determining if a motor torque is within a predetermined target in step S2 wherein when motor torque=predetermined target then; determining if a motor temperature is within a predetermined target in step S3 wherein when motor temperature=predetermined target then; and maintaining operation of the exhaust gas recirculation pump.

An EGR device for a vehicle includes a valve driver, a pressure comparison unit, a freeze determination unit, and an EGR controller. The valve driver drives an EGR valve to open, when fuel cut has been continued for a predetermined time in a state where an engine speed of a vehicle's engine is equal to or higher than a predetermined rotational speed. The pressure comparison unit compares a pre-driving pressure of an engine's intake pipe with a post-driving pressure of the intake pipe. The freeze determination unit sets a flag indicating that the EGR valve is frozen when a difference between the pre-driving pressure and the post-driving pressure is less than a predetermined value and an external temperature is less than a threshold. When the flag has been set, the EGR controller sets a control state of the EGR valve to a closed state and stops EGR control.

An EGR device for a vehicle includes a valve driver, a pressure comparison unit, a freeze determination unit, and an EGR controller. The valve driver drives an EGR valve to open, when fuel cut has been continued for a predetermined time in a state where an engine speed of a vehicle's engine is equal to or higher than a predetermined rotational speed. The pressure comparison unit compares a pre-driving pressure of an engine's intake pipe with a post-driving pressure of the intake pipe. The freeze determination unit sets a flag indicating that the EGR valve is frozen when a difference between the pre-driving pressure and the post-driving pressure is less than a predetermined value and an external temperature is less than a threshold. When the flag has been set, the EGR controller sets a control state of the EGR valve to a closed state and stops EGR control.

A diagnostic system and method that (a) that uses models indicative of both successful firing and skips to determine if cylinders of a skip fire controlled internal combustion engine have successfully fired or successfully skipped and (b) uses filtered exhaust gas pressure readings for detecting faults associated with EGR systems and/or turbocharger systems.