A method of controlling a rate of warm-up of an internal combustion engine fluidly connected to an exhaust system is disclosed. The method includes identifying a cold-start of the engine. The method also includes regulating, in response to the identified cold-start of the engine, an exhaust pressure modulation (EPM) valve arranged in a main exhaust passage of the exhaust system. The main exhaust passage channels engine exhaust gas to the ambient. Such regulation of the EPM valve will restrict a flow of the engine exhaust gas to the ambient and increase exhaust gas backpressure in the exhaust system up to a predetermined pressure value. Furthermore, the subject regulation of the EPM valve will increase a load on and the rate of warm-up of the engine. A vehicle having an engine and a controller programmed to control a rate of the engine's warm-up of according to the method is also disclosed.

A method for automatically changing the engine exhaust sound in conjunction with the traveling mode implemented by the exhaust system applied to the vehicle may vary the valve opening of an electronic variable valve provided in a first tail pipe of first and second tail pipes of muffler discharging the exhaust gas coming from an engine by a mode recognition logic connected to an engine ECU to the atmosphere, and control the variation of the valve opening with the engine torque and the engine RPM based on a change in an accelerator pedal stroke in any one of a SMART DRIVE MODE-ECO state, a SMART DRIVE MODE-COMFORT state, and a SMART DRIVE MODE-SPORT state, implementing a quiet engine exhaust sound and a sporty engine exhaust sound depending on various vehicle traveling states provided by the SMART DRIVE MODE and increasing vehicle/engine outputs.

A method for automatically changing the engine exhaust sound in conjunction with the traveling mode implemented by the exhaust system applied to the vehicle may vary the valve opening of an electronic variable valve provided in a first tail pipe of first and second tail pipes of muffler discharging the exhaust gas coming from an engine by a mode recognition logic connected to an engine ECU to the atmosphere, and control the variation of the valve opening with the engine torque and the engine RPM based on a change in an accelerator pedal stroke in any one of a SMART DRIVE MODE-ECO state, a SMART DRIVE MODE-COMFORT state, and a SMART DRIVE MODE-SPORT state, implementing a quiet engine exhaust sound and a sporty engine exhaust sound depending on various vehicle traveling states provided by the SMART DRIVE MODE and increasing vehicle/engine outputs.

A gaseous fuel engine system includes an exhaust controller coupled with a temperature sensor and a NOx sensor, and structured to actuate open an electrically actuated bypass valve to bypass an oxidation catalyst with exhaust, based on an exhaust temperature and an exhaust NOx amount to mitigate production of yellow smoke. Yellow smoke mitigation logic may run during startup and when the gaseous fuel engine is in a lower part of an engine load range. The yellow smoke mitigation logic can be selectively triggered in response to transient engine load increases when the gaseous fuel engine is operating in an upper part of an engine load range.

A gaseous fuel engine system includes an exhaust controller coupled with a temperature sensor and a NOx sensor, and structured to actuate open an electrically actuated bypass valve to bypass an oxidation catalyst with exhaust, based on an exhaust temperature and an exhaust NOx amount to mitigate production of yellow smoke. Yellow smoke mitigation logic may run during startup and when the gaseous fuel engine is in a lower part of an engine load range. The yellow smoke mitigation logic can be selectively triggered in response to transient engine load increases when the gaseous fuel engine is operating in an upper part of an engine load range.

A method is provided for preventing oil escape into an exhaust gas during operation of a turbocharged engine. The method includes providing pressurized fluid to an area sealing off a bearing housing of an axial turbine unit from an adjacent exhaust conduit downstream of the axial turbine unit, and detecting a malfunction in the provision of pressurized fluid. Further to this, the method includes the step of, in response to such malfunction detection, controlling an exhaust pressure increasing device arranged downstream of the axial turbine unit for increasing the pressure inside the exhaust conduit upstream of the exhaust pressure increasing device.

A method is provided for preventing oil escape into an exhaust gas during operation of a turbocharged engine. The method includes providing pressurized fluid to an area sealing off a bearing housing of an axial turbine unit from an adjacent exhaust conduit downstream of the axial turbine unit, and detecting a malfunction in the provision of pressurized fluid. Further to this, the method includes the step of, in response to such malfunction detection, controlling an exhaust pressure increasing device arranged downstream of the axial turbine unit for increasing the pressure inside the exhaust conduit upstream of the exhaust pressure increasing device.

Provided is a diesel engine capable of regenerating a DPF even during no-load and/or light-load operation. In a DPF regeneration process, opening-degree reduction control S2 for an exhaust-air throttle valve is performed after a start condition S1 of the regeneration process of the DPF in which PM is deposited is satisfied. When exhaust air reaches a temperature equal to or higher than a predetermined after-injection permissible temperature TA, after-injection control is subsequently started S5. Post-injection control is started S7 after the exhaust air reaches a temperature equal to or higher than a predetermined post-injection permissible temperature TP by combustion of after-injection fuel. The PM deposited in the DPF is incinerated by the exhaust air increased in temperature by catalytic combustion of post-injection fuel in a valve downstream-side DOC.

Provided is a diesel engine capable of regenerating a DPF even during no-load and/or light-load operation. In a DPF regeneration process, opening-degree reduction control S2 for an exhaust-air throttle valve is performed after a start condition S1 of the regeneration process of the DPF in which PM is deposited is satisfied. When exhaust air reaches a temperature equal to or higher than a predetermined after-injection permissible temperature TA, after-injection control is subsequently started S5. Post-injection control is started S7 after the exhaust air reaches a temperature equal to or higher than a predetermined post-injection permissible temperature TP by combustion of after-injection fuel. The PM deposited in the DPF is incinerated by the exhaust air increased in temperature by catalytic combustion of post-injection fuel in a valve downstream-side DOC.

A valve comprises a coupling device having a driven member bound to the drive shaft of a flap, a driving member bound to an output shaft of an actuator, and an elastic member. The driving member comprises attachments that hooks up the elastic member to the driving member in a temporary position in which the elastic member is elastically loaded. The driven member comprises at least one release member that at least partly releases the elastic member of the attachments when the coupling device is brought to an intermediate state or the elastic member, when the coupling device is in the intermediate state, may be at least partly released from the attachments. The elastic member once released, adopts a definitive use position under the effect of relaxation of the elastic load, the coupling device then adopting the operational state.