A preheating control for controlling an energization of a heater is executed so that a sensor element of an exhaust gas sensor is preheated within a temperature range in which no element crack caused by water occurs until a predetermined preheating period elapses after an engine starts. In performing the preheating control, first, an energization duty of the heater is set to a preheating promotion energization duty to promptly raise a temperature of the sensor element until it is determined that the temperature of the sensor element reaches a predetermined upper limit temperature. After it is determined that the temperature of the sensor element reaches the upper limit temperature, the energization duty of the heater is set so that the temperature of the sensor element is maintained at the upper limit temperature to sufficiently raise the temperature of the overall sensor element during the preheating control.

A method is disclosed for regulating an exhaust after-treatment (AT) system for a diesel engine. The method includes detecting the engine's cold start when the engine's exhaust gas flow directed into the AT system is at a temperature below a threshold value. The method also includes determining flow-rates of the engine's exhaust gas and its fuel supply. The method additionally includes determining a magnitude of exhaust gas energy using the determined exhaust gas flow-rates and the fuel supply over an elapsed time following the cold start. The method also includes integrating a detected temperature of the exhaust gas over the elapsed time and comparing the determined magnitude of exhaust gas energy with the integrated temperature. Furthermore, the method includes regulating operation of the AT system using the determined exhaust gas temperature when the determined magnitude of exhaust gas energy is within a predetermined value of the integrated exhaust gas temperature.

A method for testing a sensor positioned downstream of an engine. The method includes motoring the engine, receiving a signal indicative of a value from the sensor, and determining whether the value is inside or outside of an established range. The established range is based on a known characteristic of an exhaust gas exiting from the engine as it is motoring.

A data transmission system comprising an Automotive Sensor Network System (ASNS) connected to a plurality of source locations via a common bus, wherein the ASNS is configured to ascertain the source from which the data-frames and first package checksum are received and based on the ascertainment of the source, appropriate decoding methods are used to calculate the ASNS location data-frame checksums and the ASNS location package checksums. A higher order redundancy check is done over a series of data-frames to detect errors in the reception caused by temporary high interference that may exist in the transmission path.

Methods and systems are provided for diagnosing an intake oxygen sensor. In one example, a method may include indicating degradation of an intake oxygen sensor based on a first time constant of an output of the intake oxygen sensor and a second time constant of an output of a throttle inlet pressure sensor. The method may further include adjusting EGR flow based on the output of the intake oxygen sensor and the output of the throttle inlet pressure sensor when the intake oxygen sensor is not degraded.

An estimation unit calculates an estimated value of oxygen concentration in an exhaust passage on the basis of a target injection amount of a fuel injection valve and an air intake amount of an engine. A first determination unit determines the relationship of a detected value to the estimated value of the oxygen concentration, in both a fuel-injecting state and a non-fuel-injecting state. For each of a plurality of cylinders, a second determination unit acquires crankshaft angular acceleration during the expansion strokes of the cylinders in the fuel-injecting state, and determines the relationship of each angular acceleration to the average value of all of the angular accelerations. An abnormality determination unit determines whether or not there is an abnormality in an engine system on the basis of the determination results of the first and second determination units.

A method for detecting errors in a sensor at a gas cylinder is implemented by a pressure estimation computing device including a processor and a memory device coupled to the processor. The method includes receiving a first pressure measurement from a first sensor associated with a gas cylinder, receiving a design schema describing an intake manifold, the intake manifold included within the gas engine, segmenting the design schema into a plurality of segments, defining a fluid dynamics model associated with each of the plurality of segments, defining a plurality of interconnected 2-port elements based on the plurality of fluid dynamics models, estimating a second pressure measurement for the gas cylinder based on the plurality of interconnected 2-port elements, comparing the first pressure measurement to the second pressure measurement, and determining that the first sensor is in an anomalous state.

A heater control apparatus of a fuel filter for a vehicle includes a heater mounted within a fuel filter; a relay for a heater power source supplying or interrupting power of a battery to or from the heater; a fuel temperature detection sensor mounted on an engine and detecting a temperature of a fuel; and an engine electronic control unit (ECU) for switching on and off the relay based on a detection signal of the fuel temperature detection sensor.

Methods and systems for predicting at least one temperature along a fluid flow path of a fluid flow system having a heater disposed in the fluid flow path are provided. In one example, a method includes: obtaining at least one input, wherein the at least one input includes a setpoint, a mass flow rate, an inlet temperature, or a combination thereof; calculating a temperature associated with the heater based on a predefined model and the at least one input; and setting a value of the at least one temperature along the fluid flow path to the temperature of the heater.

Disclosed is a method for diagnosing a speed/position sensor of an internal combustion engine, of the type including a toothed wheel, which rotates as one with a shaft, and a matter detector, which is arranged so as to be fixed opposite the toothed wheel and controls a base of a transistor. The method includes: detecting a short circuit between an output of the speed/position sensor and a power supply; and testing for excess current consumption by a power supply of the speed/position sensor when the transistor is activated. If the test is positive, the short circuit is identified between the power supply of the speed/position sensor and the output of the speed/position sensor. Alternatively, if the test is negative, the short circuit is identified between another power supply and the output of the speed/position sensor.