An Exhaust Gas Recirculation (EGR) effective flow diagnosis method includes: measuring an EGR gas temperature by an EGR gas temperature sensor under an EGR gas temperature rise condition of an EGR system on an intake line; determining the degree of the EGR gas temperature rise; and determining whether an EGR effective flow is excessive or insufficient according to the degree of the EGR gas temperature rise.

An air intake amount measurement device 200 includes an intake distributor 3 distributing intake air CYL to cylinders 11, 12, 13, and 14, a temperature detector 202 detecting a temperature Ti of the intake air CYL, a pressure detector 201 for detecting a pressure Pi of intake air CL, and a computing unit 100 that computes an air intake amount mfcyl of the intake air CYL on the basis of the temperature Ti transmitted from the temperature detector 202 and the pressure Pi transmitted from the pressure detector 201. The temperature detector 202 detects the temperature Ti of the intake air CYL at a region W spanning, out of an inside of the intake distributor 3, a first branch portion 31 and a second branch portion 32.

An air intake amount measurement device 200 includes an intake distributor 3 distributing intake air CYL to cylinders 11, 12, 13, and 14, a temperature detector 202 detecting a temperature Ti of the intake air CYL, a pressure detector 201 for detecting a pressure Pi of intake air CL, and a computing unit 100 that computes an air intake amount mfcyl of the intake air CYL on the basis of the temperature Ti transmitted from the temperature detector 202 and the pressure Pi transmitted from the pressure detector 201. The temperature detector 202 detects the temperature Ti of the intake air CYL at a region W spanning, out of an inside of the intake distributor 3, a first branch portion 31 and a second branch portion 32.

A controller for a motor vehicle having an internal combustion engine, and a device for detecting a fire in a fluid conduit, the device having a fluid state sensor for detecting a state variable of a fluid that is conducted in the fluid conduit, are provided. The determination of a fire situation is performed in a manner dependent on a signal of the fluid state sensor.

Methods and systems are provided for diagnostics of exhaust gas recirculation (EGR) components including an EGR pressure sensor. In one example, a method for an exhaust gas recirculation (EGR) system of a vehicle comprises diagnosing an excessive EGR flow rate via an MAP-MAF strategy, the MAP-MAF strategy including estimating an EGR flow rate based on a difference between an output of a manifold absolute pressure (MAP) sensor of the vehicle and an output of a mass airflow (MAF) sensor of the vehicle; and in response to stable intrusive conditions being met, intrusively commanding an EGR valve of the EGR system to a closed position to confirm the diagnosed excessive EGR flow rate. If the excessive flow is detected after the EGR valve is commanded to the closed position, a diagnostic code may be set.

An EGR estimation method for estimating an EGR rate in an intake and exhaust system of an internal combustion engine, the intake and exhaust system including: an intake system including an air cleaner and an intake passage that connects the air cleaner and the engine, an exhaust system including an exhaust passage, and a supercharger that is provided in the intake passage and the exhaust passage, the intake and exhaust system including an EGR device including an EGR passage that connects the intake passage and the exhaust passage and an EGR valve, and the intake system including an intake bypass passage that connects an upstream pressure portion and a downstream pressure portion of the supercharger and a recirculation valve. The EGR estimation method includes: opening the recirculation valve during supercharging, and estimating the EGR rate after closing the EGR valve based on the EGR rate before opening the recirculation valve.

Methods and systems are provided for diagnostics of exhaust gas recirculation (EGR) components including an EGR pressure sensor. In one example, a method may include comparing a current relationship between an output of the EGR pressure sensor and a manifold air pressure (MAP) and a pre-calibrated relation between the output of the EGR pressure sensor and the MAP to detect degradation of the EGR pressure sensor.

Methods and systems are provided for diagnostics of exhaust gas recirculation (EGR) components including an EGR pressure sensor. In one example, a method may include comparing a current relationship between an output of the EGR pressure sensor and a manifold air pressure (MAP) and a pre-calibrated relation between the output of the EGR pressure sensor and the MAP to detect degradation of the EGR pressure sensor.

A method for determining the recycled air flow rate and oxygen quantity at the inlet of an internal combustion engine cylinder. The method involves measuring pressure in each cylinder during a compression phase and calculating the mass of gas in each cylinder based on the measured pressure, volume and temperature variation for an angular variation of the crankshaft, heat capacity, and heat losses. The method further involves determining the mass of gas in all cylinders over a full combustion cycle as well as in the recycled exhaust.

A method for determining the recycled air flow rate and oxygen quantity at the inlet of an internal combustion engine cylinder. The method involves measuring pressure in each cylinder during a compression phase and calculating the mass of gas in each cylinder based on the measured pressure, volume and temperature variation for an angular variation of the crankshaft, heat capacity, and heat losses. The method further involves determining the mass of gas in all cylinders over a full combustion cycle as well as in the recycled exhaust.