A system and method of integrating an engine having dynamic skip fire control with an exhaust gas recirculation system in a turbocharged internal combustion engine is described. An engine control system determines an appropriate firing pattern based at least in part on a desired exhaust gas recirculation flow rate. Signals from sensors in the intake manifold and exhaust system may also be used as part of a feedback loop to determine a desired exhaust gas recirculation flow rate.

A water ingestion control system for an internal combustion engine can include a snorkel, at least one closure structure, a choking valve, and a controller. The snorkel can include an air intake opening and at least one evacuation inlet that can be selectively opened and closed by the closure structure. The choking valve can be located between the air intake opening and an air box and selectively open and close fluid communication between the snorkel and the air box. When in a closed state, the choking valve can close fluid communication between the snorkel and the air box and prevents fluid in the snorkel from flowing into the air box and the engine. The controller can be configured to place the choking valve in the closed state when the controller receives data indicative of the presence of water in the snorkel.

The present invention obtains a humidity measuring device capable of performing self-diagnosis with high reliability. This humidity measuring device 20 has a diagnosis processing unit 25 for performing self-diagnosis by using gas temperatures and gas humidities before and after a gas in an ambient atmosphere to be measured is heat-controlled. The diagnosis processing unit has a diagnosis start determining unit 26 for determining whether the self-diagnosis can be started on the basis of an exchange state in the ambient atmosphere to be measured and the gas temperature and the gas humidity before the gas in the ambient atmosphere to be measured is heat-controlled, and a diagnosis continuation determining unit 28 for determining whether the self-diagnosis can be continued on the basis of the gas temperature and the gas humidity that are heat-controlled during the self-diagnosis.

Methods and systems are provided for determining changes in a flow area of an exhaust gas recirculation (EGR) valve for EGR flow estimates due to soot accumulation on the EGR valve. In one example, a method includes indicating soot accumulation on the EGR valve based on a difference in EGR flow estimated with an intake oxygen sensor and with a pressure sensor coupled across the EGR valve. The determination of the difference of the EGR flow estimates may occur when the engine is not boosted.

A system and method of integrating an engine having dynamic skip fire control with an exhaust gas recirculation system in a turbocharged internal combustion engine is described. An engine control system determines an appropriate firing pattern based at least in part on a desired exhaust gas recirculation flow rate. Signals from sensors in the intake manifold and exhaust system may also be used as part of a feedback loop to determine a desired exhaust gas recirculation flow rate.

A determination device determining malfunction of a humidity sensor includes a malfunction determination portion. The humidity sensor includes a humidity detector, a temperature detector and a heater. The humidity detector has a humidity-sensitive film in an intake passage and detects a relative humidity of intake air taken into an internal combustion engine for a vehicle. The temperature detector detects a temperature of the humidity-sensitive film. The heater heats the humidity-sensitive film and the temperature of the humidity-sensitive film is increased by the heater. The malfunction determination portion estimates an estimated relative humidity at a subsequent temperature from an original relative humidity and the subsequent temperature, and compares the estimated relative humidity at the subsequent temperature and an actual subsequent relative humidity to determine malfunction of the humidity detector.

Embodiments for diagnosing a humidity sensor are provided. One example method comprises, responsive to a humidity sensor test cycle, pumping air conditioning and windshield washer gas flows past a humidity sensor, and indicating humidity sensor degradation based on a response of the humidity sensor to the air conditioning and windshield washer gas flows. In this way, degradation of the humidity sensor may be indicated if the humidity sensed by the humidity sensor does not change responsive to the humidity sensor test cycle being initiated.

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.

The purpose of this invention obtain a physical-quantity detection device, the external shape of the housing of which can be reduced in size. Said physical-quantity detection device, which detects a plurality of physical quantities of a gas being measured that flows through a main channel, is characterized by having a housing positioned inside said main channel, a circuit board insert-molded into said housing, and a plurality of detection sensors mounted on both sides of the circuit board.

Based on a determination result by a nitrogen concentration determination section, an electronic control unit changes a switching line used to switch between a differential state and a non-differential state of a differential mechanism and a gear shift line used to switch a gear stage of an automatic transmission mechanism. In conjunction with a change of an engine operation point to a high-speed side in a nitrogen-enriched state of intake air, a first motor rotational speed in the differential state of the differential mechanism becomes higher than that in a non-enriched state of the intake air. Thus, corresponding to the above, the differential mechanism is appropriately switched between the differential state and the non-differential state, and the gear stage of the automatic transmission mechanism is appropriately switched.