An embodiment system for mild hybrid starter and generator (MHSG) failure diagnosis of a mild hybrid vehicle includes a data detection part configured to detect data for determining whether to activate a catalyst, and a controller configured to determine whether there is an MHSG failure using a deviation between a required torque and an actual operating torque of an MHSG after determining whether catalyst activation is needed and whether to start a stage of the MHSG failure diagnosis based on the data detected by the data detection part.

Disclosed are a hybrid electric vehicle capable of controlling starting of an engine in order to more efficiently realize heating and an engine control method therefor. The method of controlling an engine of a hybrid electric vehicle of the disclosure includes determining whether the engine is in a warmed-up state when a fully automatic temperature control system makes a heating request, making an engine startup request for heating to an engine management system configured to control the engine when the engine is in the warmed-up state, and selectively requesting the engine management system to perform cylinder deactivation (CDA) control on at least some of a plurality of cylinders of the engine depending on whether the engine is in an idling state.

In exemplary embodiments, methods and systems are provided for controlling emissions for a drive system for a vehicle. In one embodiment, the system includes: one or more first sensors configured to measure an engine temperature pertaining to an engine of the vehicle; one or more second sensors configured to measure an ambient temperature surrounding the vehicle; one or more third sensors configured to detect an amount of running time in which the engine has been running; and a processor coupled to the one or more first sensors, the one or more second sensors, and the one or more third sensors and configured to at least facilitate controlling emissions for the drive system based on the engine temperature, the ambient temperature, and the amount of running time in which the engine has been running.

A variety of methods and arrangements for reducing noise, vibration and harshness (NVH) in a skip fire engine control system are described. In one aspect, a firing sequence is used to operate the engine in a skip fire manner. A smoothing torque is determined that is applied to a powertrain by an energy storage/release device. The smoothing torque is arranged to at least partially cancel out variation in torque generated by the skip fire firing sequence. Various methods, powertrain controllers, arrangements and computer software related to the above operations are also described.

Methods and systems are provided for a coolant system. In one example, a method may include diagnosing a condition of a pump of the coolant system based on a temperature change of coolant. The diagnostic may determine if the pump is stuck on or off.

A method for stopping an engine within a desired crankshaft angular range is disclosed. In one example, the method may take no control actions if it is determined that the engine will stop within the desired crankshaft angular range. However, if it is determined that the engine may stop outside of the desired crankshaft angular range, expansion combustion may be initiated in a cylinder so that the engine stops in a desired crankshaft angular range.

If an engine coolant temperature is equal to or lower than a first low-temperature determination value and a battery temperature is equal to or lower than a second low-temperature determination value when a request to start up an engine is made, the advancement driving of a variable valve operating mechanism is first started. Then, when an advancement amount of the variable valve operating mechanism later becomes equal to or larger than a prescribed startup start determination value, is started.

The disclosure relates to a supercharged, direct-injection internal combustion engine having an intake system for the supply of charge air and having an exhaust-gas discharge system for the discharge of exhaust gas and having at least two series-connected exhaust-gas turbochargers which each comprise a turbine arranged in the exhaust-gas discharge system and a compressor arranged in the intake system and of which a first exhaust-gas turbocharger serves as a low-pressure stage and a second exhaust-gas turbocharger serves as a high-pressure stage, a first bypass line being provided which branches off from the exhaust-gas discharge system between the first turbine and the second turbine so as to form a first junction point.

Switchable radiative energy harvesting systems and methods of harvesting radiation are disclosed. A system includes an optical filter that includes at least one of an active material and a passive material. The optical filter is switchable between a shield mode and a harvesting mode such that the at least one of the active material and the passive material is in a reflecting state during the shield mode such that the optical filter blocks passage of radiation from a thermal emitter to a thermophotovoltaic cell and a transmitting state during the harvesting mode such that that the optical filter allows the radiation to pass from the thermal emitter to the thermophotovoltaic cell.

Methods and systems are provided for controlling a vehicle including a manual transmission to prevent cold-start drive-away. In one example, a method for a vehicle with a driver clutch pedal may include preventing one of a clutch coupled between an input of a transmission and an engine output from closing and a driver-operated gearshift lever for adjusting a gear of the transmission from coming out of neutral in response to a catalyst light-off condition.