Examples of the present disclosure describe systems and methods for determining an estimated ambient air temperature in an environment in which a vehicle is operating. The estimated ambient air temperature may be compared to an ambient temperature sensor value. The comparison may be used to determine whether an ambient air temperature sensor of the vehicle is functioning properly or if an error notification or fault code should be triggered.

Examples of the present disclosure describe systems and methods for determining a state of an air diverter valve of an air induction system of a vehicle. The determined state of the air diverter valve may be based on an intercooler-based estimated ambient air temperature and a comparison between an ambient air temperature sensor value and a pre-compressor sensor value.

A system includes an engine adapted to output a torque, a parasitic load adapted to receive a portion of the torque from the engine, and a controller communicably coupled to the parasitic load. The controller is configured to determine an actual exhaust temperature value of an exhaust gas flow exiting the engine and a minimum fuel amount to be injected into the engine. The controller is configured to compare the actual exhaust temperature value with an exhaust temperature threshold value of the exhaust gas flow to determine a first difference between the actual exhaust temperature value and the exhaust temperature threshold value. The controller is configured to determine a target torque output of the engine based on the first difference and the minimum fuel amount. The controller is configured to cause the torque to be increased to attain the target torque output using the parasitic load.

An engine system includes an engine, an intake line, an exhaust line, a turbocharger, a water-cooled intercooler, a high-pressure Exhaust Gas Recirculation (EGR) system which includes a high-pressure EGR line, a high-pressure EGR cooler, and a high-pressure EGR valve, a low-pressure EGR system which includes a low-pressure EGR line, and a low-pressure EGR cooler, a radiator which cools the coolant, a low-pressure EGR cooling line, an intercooler cooling line, a low-pressure EGR cooling valve, an intercooler cooling valve, an electric water pump, a driving information detector which detects driving information of a vehicle including an outside air temperature, a temperature of the intake gas supplied to the engine and a coolant temperature, and a controller which controls the low-pressure EGR cooling valve, the intercooler cooling valve, the high-pressure EGR valve and the electric water pump based on the driving information detected by the driving information detector.

Methods and systems are described for diagnosing degradation of a vacuum actuator in an engine system. An example method comprises indicating degradation of the vacuum actuator based on an estimate of flow of air into and out of a vacuum reservoir. The estimate is further based on flow of air generated via each of an aspirator in the intake system, an actuation of the vacuum actuator, and leakage during the actuation of the vacuum actuator.

The present invention provides a novel combination of devices to measure and transmit to an electronic controller data pertaining to differential pressures, temperatures, regeneration status, exhaust content, accumulated gas consumption and substitute fuel consumption. The electronic controller compares the data to thresholds; when the controller receives signals indicating these thresholds or limits are met, the controller causes the gas substitution rate to be diminished or set to zero until after-treatments elements are fully regenerated thereby facilitating integration of a mixed fuel system with an application internal combustion engine.

Various methods and systems are provided for a multi-fuel capable engine. In one example, a system comprises an engine having at least one cylinder controlled via an intake valve, a first fuel system to deliver liquid fuel and a second fuel system to deliver gaseous fuel to the at least one cylinder, a variable valve timing actuation system to adjust one or more of an opening or a closing timing of the intake valve, and a controller. The controller is configured to, during a liquid fuel only mode, adjust the variable valve timing actuation system to close the intake valve at a first timing based at least on engine load, and during a multi-fuel mode, adjust the variable valve timing actuation system to close the intake valve at a second timing.

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 controlling an air-cooled internal combustion engine (ICE) of a motor vehicle controlled by an electronic control unit, includes: activating the electronic control unit; zeroing stored values of temperature of the ICE and the filtered filtering coefficient; in one iteration, —determining whether the ICE is operating, determining a filtering coefficient and a temperature setpoint, —determining a filtered filtering coefficient based on the filtering coefficient and the stored filtered filtering coefficient value, —determining temperature of the ICE according to the coefficient, temperature setpoint and stored temperature of the ICE, —determining whether the ICE is moving and whether the difference between engine temperature and admitted air temperature is below a threshold, ⋅ if not, storing the filtered filtering coefficient and the temperature of the ICE, then beginning a new iteration, and ⋅ if so, transmitting a signal authorizing the shutdown of the electronic control unit.

To provide a controller and a control method for an internal combustion engine capable of reducing the calculation error of recirculation exhaust gas amount due to changes with time of the internal combustion engines, and humidity change of intake air, and also capable of reducing the calculation error of recirculation exhaust gas amount at transient operation. The controller and the control method for the internal combustion engine calculates humidity detecting EGR rate based on intake-air humidity and manifold humidity, calculates humidity detecting opening area which realizes humidity detecting recirculation flow rate calculated based on humidity detecting EGR rate, calculates learned opening area corresponding to present opening degree of EGR valve using learning value of opening area calculated based on humidity detecting opening area, and calculates flow rate of recirculation exhaust gas for control based on learned opening area.