Systems, methods and apparatus for controlling operation of dual fuel engines are disclosed that regulate the fuelling amounts provided by a first fuel and a second fuel during operation of the engine. The first fuel can be a liquid fuel and the second fuel can be a gaseous fuel. The fuelling amounts are controlled to improve operational outcomes of the duel fuel engine.

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.

A pre-overheat system for minimizing engine damage due to overheating includes a temperature sensor and a warning system that alerts the vehicle's operator (using light, sound, vibration, etc.) if temperatures exceed steady-state temperatures and/or reach higher pre-overheat temperatures. Steady-state temperatures are measurable when the vehicle is functioning normally (especially its cooling system) and is running in normal environmental conditions, but is lower than a redzone overheat temperature for the particular vehicle. When the redzone overheat temperature is reached, the vehicle has gotten too hot and is likely to sustain irreparable damage. The operator can reduce or prevent damage to the vehicle by taking corrective action (such as stopping and checking coolant level and clearing debris from clogged vents and screens) before the vehicle is overheated. A shutdown mechanism can shut off the vehicle before the redzone overheat temperatures are reached.

A method for detecting a combustion process of an internal combustion engine of a hybrid vehicle includes the steps of acquiring a rotational speed signal representing a rotational speed of the crankshaft, acquiring a crankshaft angle signal representing a crankshaft angle of the crankshaft, and determining, based on the rotational speed signal and the crankshaft angle signal, whether a combustion occurs in the internal combustion engine. A control device for detecting a combustion process of an internal combustion engine of a hybrid vehicle is also provided.

An engine system incorporating an engine, one or more sensors, and a controller. The controller may be connected to the one or more sensors and the engine. The one or more sensors may be configured to sense one or more parameters related to operation of the engine. The controller may incorporate an air-path state estimator configured to estimate one or more air-path state parameters in the engine based on values of one or more parameters sensed by the sensors. The controller may have an on-line and an off-line portion, where the on-line portion may incorporate the air-path state estimator and the off-line portion may configure and/or calibrate a model for the air-path state estimator.

An internal combustion engine comprises an exhaust purification catalyst arranged in an exhaust passage of the internal combustion engine and being able to store oxygen in inflowing exhaust gas and an air-fuel ratio sensor arranged at a downstream side of the exhaust purification catalyst in a direction of exhaust flow and detecting an air-fuel ratio of exhaust gas flowing out from the exhaust purification catalyst and stops or decreases a feed of fuel to a combustion chamber as fuel cut control. The abnormality diagnosis system calculates a characteristic of change of an air-fuel ratio based on an output air-fuel ratio output from the air-fuel ratio sensor at the time when the output air-fuel ratio first passes a part of an air-fuel ratio region of a stoichiometric air-fuel ratio or more after an end of the fuel cut control, and diagnoses abnormality of the air-fuel ratio sensor based on the characteristic of change of the air-fuel ratio. As a result, the diagnosis system can diagnose the abnormality of deterioration of response of the downstream side air-fuel ratio sensor when necessary without fail when performing fuel cut control.

A misfire detecting system for an engine of a vehicle that detects a misfire of the engine is provided, which includes a processor. The processor determines whether a misfire has occurred by examining whether a fluctuation of a crank angle of the engine is equal to or greater than a determination reference value, acquires a value relating to a density of intake air introduced into the engine, and adjusts the determination reference value according to the value related to the density.

An exhaust gas purification system comprises an exhaust gas purification device which is arranged in an exhaust gas route of an engine, renewing devices for burning and removing a particulate matter within the exhaust gas purification device, renewal advance notifying means which is actuated in the case that a clogged state of the exhaust gas purification device becomes equal to or more than a prescribed level, and renewal informing means which informs of a fact that the renewing devices are under operation. The renewal advance notifying means is actuated before actuating the renewing devices.

A work vehicle having a plurality of working modes allowing working in accordance with a load state includes an engine, an exhaust gas purification apparatus, a reducing agent tank, a state determination portion, and an engine control unit. The exhaust gas purification apparatus purifies a nitrogen oxide in an exhaust gas. The reducing agent tank stores a reducing agent. The state determination portion determines a state of the reducing agent. The engine control unit controls output of the engine with the use of a restricted-operation engine output torque curve in which horsepower output from the engine is lower than horsepower output from the engine at the time when each of the plurality of working modes is selected, when a state of the reducing agent is equal to or lower than a reference value.

A heater is provided that includes at least one resistive heating element having a material with a non-monotonic resistivity vs. temperature profile and exhibiting a negative dR/dT characteristic over a predetermined operating temperature range along the profile. The heater can include a plurality of circuits disposed in a fluid path to heat fluid flow.