Methods and systems are provided for an EGR cooler having first and second coolant jackets fluidly coupled to first and second coolant systems, respectively. In one example, the first and second coolant jackets are hermetically sealed from one another. Furthermore, the second coolant jacket protrudes into a portion of an exhaust gas passage directly downstream of an exhaust aftertreatment device.

A method of controlling exhaust gas recirculation (EGR) for controlling recirculation of exhaust gas discharged from a combustion chamber of an engine includes: a data obtaining operation of obtaining data about an engine state and a gas supply state; a current EGR rate calculating operation of calculating a current EGR rate of supply gas based on the data; a demand EGR rate setting operation of setting a demand EGR rate matched with the data in a pre-made target EGR rate map; an error calculating operation of calculating a difference between the demand EGR rate and the current EGR rate; and a control operation of making the current EGR rate follow the demand EGR rate by changing a recirculation rate of the exhaust gas by adjusting an inhalation side pressure of the supply gas according to the difference.

Methods and systems are provided for adjusting engine operation based on wirelessly received weather data in conjunction with engine sensor outputs. In one example, a method may comprise receiving a first measurement of a weather parameter from one or more engine sensors and a second measurement of the weather parameter from weather data, the weather data provided by a wireless weather service. The method may further comprise determining accuracies for the first and second measurements, generating an estimate of the weather parameter based on the accuracies of the first and second measurements, and adjusting at least one engine operating parameter based on the generated estimate.

Methods and systems for an engine intake system are provided. In one example, a system includes a first charge air cooler arranged upstream of a second charge air cooler. The first charge air cooler is configured to provide thermal transfer between a compressed charge air and a fresh intake air.

Methods and systems for an engine intake system are provided. In one example, a system includes a first charge air cooler arranged upstream of a second charge air cooler. The first charge air cooler is configured to provide thermal transfer between a compressed charge air and a fresh intake air.

Methods and systems are provided for a comprex charger. In one embodiment, a comprex charger is integrally arranged with an electric machine and shares a cooling arrangement therewith.

Methods and systems are provided for a comprex charger. In one embodiment, a comprex charger is integrally arranged with an electric machine and shares a cooling arrangement therewith.

A controller calculates a specific humidity of an intake air based on a relative humidity of the intake air, an intake air temperature, and an intake air pressure. Then the controller calculates a water vapor amount in the intake air based on the specific humidity and a mass flow rate of the intake air obtained from an air intake rate. By calculating the water vapor amount in the intake air based on information that directly represents the status of the intake air, this water vapor amount may be calculated more accurately. As a result, a generation amount of condensed water may be estimated more accurately. Therefore, accumulation of condensed water may be suppressed while recirculating as much of a low pressure exhaust gas as possible, and thus fuel economy may be sufficiently improved.

A controller calculates a specific humidity of an intake air based on a relative humidity of the intake air, an intake air temperature, and an intake air pressure. Then the controller calculates a water vapor amount in the intake air based on the specific humidity and a mass flow rate of the intake air obtained from an air intake rate. By calculating the water vapor amount in the intake air based on information that directly represents the status of the intake air, this water vapor amount may be calculated more accurately. As a result, a generation amount of condensed water may be estimated more accurately. Therefore, accumulation of condensed water may be suppressed while recirculating as much of a low pressure exhaust gas as possible, and thus fuel economy may be sufficiently improved.

A method for operating an engine, comprising port injecting a first quantity of a first gaseous fuel in a cylinder cycle and direct injecting a second quantity of a secondary injectant in the cylinder cycle as a function of a desired air-to-fuel ratio (AFR), the desired AFR based on a temperature of an engine cylinder valve. The desired AFR may be outside the AFR range available during natural gas combustion alone and thus allows for cooler engine operation.