Methods and systems are provided for monitoring a change in exhaust particulate filter (PF) soot load during an engine non-combusting condition. In one example, a method may include, responsive to a higher than threshold PF temperature immediately prior to an engine shutdown, estimating a rate of soot burn when the engine is no longer combusting, and estimating a soot load on the PF during and at an onset of immediately subsequent engine start based in part on the rate of soot burn.

A carbon monoxide shutoff system for an engine of a portable electrical generator has a carbon monoxide gas sensor, a microcontroller, and an output indicator. The carbon monoxide gas sensor generates an output electrical current proportional to a detected concentration of ambient carbon monoxide. The microcontroller has an input connected to the carbon monoxide gas sensor, and an output connected to an operational control of the engine. A deactivation signal generated by the microcontroller in response to detection of a deactivation condition is based upon the output electrical current from the carbon monoxide gas sensor matching predefined value and duration thresholds. The deactivation signal is operative to stop the engine.

Systems and methods for diagnosing the presence or absence of turbocharger wastegate degradation are presented. In one example, an intake manifold pressure sensor provides a basis for determining whether or not turbocharger wastegate degradation present. The turbocharged engine may be rotated in a reverse direction to assess wastegate degradation.

Various embodiments include a method for checking a sensor for soot particles in exhaust of an engine comprising: generating a sensor current between a first electrode and a second electrode of the sensor, wherein the first electrode and the second electrode define a gap through which the exhaust gas flows between the electrodes, by applying a difference in potential between the electrodes, wherein soot particles accumulate on the electrodes and, after a dwell time dependent on the preloading of the electrodes with soot particles, they move from a first electrode to the respective second electrode generating a flow of current as a measure of the quantity of soot in the stream of exhaust gas; determining whether a peak in the sensor current is measured after the switching off of the internal combustion engine; and if no peak in the sensor current is measured, flagging the particle sensor as faulty.

A pre-stoppage ignition control unit defines, as a stoppage transition air amount, an intake air amount of the engine with which the engine torque becomes the stoppage transition torque in a state in which an ignition timing of the engine is set to a predetermined self-sustaining operation ignition timing, defines, as an intermediate timing, a predetermined timing earlier than timing at which the intake air amount converges to the stoppage transition air amount during an execution period of the pre-stoppage self-sustaining operation control, sets the ignition timing of the engine in a period from the start of the pre-stoppage self-sustaining operation control to the intermediate timing to timing earlier than the self-sustaining operation ignition timing, and sets the ignition timing of the engine in the period after the intermediate timing to the self-sustaining operation ignition timing.

A system is provided for automatically shutting down an engine in response to the engine operating while in an enclosed space to prevent dangers associated with carbon monoxide accumulating in the enclosed space. The engine has an oxygen sensor in its exhaust that is configured to detect oxygen in the exhaust or ambient. A controller can be programmed to shut down the engine based on a determination that the engine is operating in a confined or enclosed space by analyzing a rate of change of the oxygen content in the exhaust or ambient, and compares the rate to a threshold. The shutdown may be commanded if the rate exceeds the threshold. In some embodiments, the shutdown may additionally be in response to a temperature of the ambient air or intake air increasing, which furthers the confidence of the determination that the engine is operating in a confined or enclosed space.

A valve timing controller includes: a driving side rotation member that rotates synchronously with a crankshaft of an internal combustion engine; a driven side rotation member that integrally rotates with a cam shaft of the internal combustion engine; a phase regulating mechanism with which a relative rotation phase of the driving and driven side rotation members around a rotation axis is set by a driving force of an electric motor; a phase sensing portion that acquires the relative rotation phase; and a phase controlling section that controls the electric motor to set the relative rotation phase based on an acquisition result by the phase sensing portion. The phase sensing portion includes a cam angle sensor, a reference determination sensor, and a pattern storage unit. The valve timing controller further includes a phase acquisition portion.

A microchip oxygen sensor for sensing exhaust gases from a combustion process, and related methods. The microchip oxygen sensor includes a dielectric substrate and a heater pattern affixed to the substrate. A first electrode is affixed to the substrate and has a first plurality of fingers forming a first comb. A second electrode is affixed to the substrate and has a second plurality of fingers forming a second comb. The second electrode is disposed in spaced relation to the first electrode such that the first and second combs face each other. A semiconducting layer is disposed over the first and second electrodes so as form a physical semiconductor bridge between the first and second electrodes. The semiconducting layer comprises an n-type semiconducting material or a p-type semiconducting material. A porous dielectric protective layer, advantageously containing a catalytic precious metal, may cover the semiconducting layer.

Systems and methods for improving operation of an engine are presented. In one example, a position of a throttle is adjusted along with other actuators to improve engine starting.

An on-demand generator starting system and method is disclosed. The generator starting system is included as part of a standby or portable generator that includes one or more outlets that provide electrical power to an electrical device. The operating system includes a generator controller that monitors for a request for power from the electrical device connected to the outlet. When the control circuit of the generator controller determines that electric power is required from the generator, the control circuit initiates operation of the internal combustion engine. After the internal combustion engine starts, the control circuit operates a relay to provide power from the generator to the outlet of the generator. When the electrical device is no longer operating, the control circuit of the generator controller terminates operation of the internal combustion engine of the generator. In this manner, the generator operates only when the electrical device is requesting electrical power.