Methods and systems are provided for opportunistically conducting an evaporative emissions test diagnostic procedure in order to indicate the presence or absence of undesired evaporative emissions in a vehicle evaporative emissions control system and fuel system. In one example, tire pressure and barometric pressure are monitored, and responsive to a tire pressure decrease in the absence of a barometric pressure increase, along with an indication that the vehicle transmission is in neutral and that the vehicle is not traveling downhill, the evaporative emissions system and fuel system may be sealed and the presence or absence of undesired evaporative emissions indicated based on a vacuum-build. In this way, an opportunistic evaporative emissions test may be conducted based on conditions favorable to conducting an emissions test procedure, and may thus increase test completion rates and reduce undesired evaporative emissions.

A method and apparatus for continually and rapidly adjusting the output torque of an engine according to a torque demand uses an active tappet to vary the instant air charge in a combustion chamber, so as to modulate engine torque during an automatic change of speed ratio. The invention allows substantially efficient combustion throughout the engine operating map. Various methods of changing the charge of air are disclosed.

A method for intelligent active engine braking using full authority active fuel management based on vehicle speed and brake pedal position. The method includes determining if the tow mode of the vehicle has been selected and enables all engine cylinders to ensure maximum engine braking capacity is available. When vehicle tow mode is not selected then the method varies engine braking capacity by disabling one or more cylinders based on the vehicle speed and brake pedal position.

A prime mover control device of a work vehicle equipped with a torque converter includes: a speed ratio calculation unit that calculates a speed ratio of the torque converter; and a rotational speed limit unit that, when a speed ratio falls within a preset speed ratio range, limits a maximum rotational speed of the prime mover to be lower as compared with a maximum rotational speed set when a speed ratio falls without the preset speed ratio range. When a state in which the speed ratio calculated by the speed ratio calculation unit falls within the preset speed ratio range is maintained for a predetermined time period, the rotational speed limit unit changes a maximum rotational speed of the prime mover to a higher maximum rotational speed than the limited maximum rotational speed limited to be lower by the rotational speed limit unit.

In order to prevent an abnormal combustion due to oil, a restriction region (B) is designated on a low-speed and high-load side of an internal combustion engine (1), and an opening of throttle valve (12) is restricted so that an engine operating condition is not observed within the restriction region (B). A predetermined designated inspection region (A) is set so as to include the restriction region (B), and it is judged whether or not the abnormal combustion actually occurred when the internal combustion engine (1) is running within the designated inspection region (A). If the abnormal combustion was detected, the restriction region (B) is expanded, meanwhile, if the abnormal combustion was not detected, the expanded restriction region (B) is gradually decreased. If the abnormal combustion occurred at a shorter interval than a threshold value, the restriction region (B) is expanded at once to a predetermined size.

A smart governor system that intercepts and adjusts throttle commands when certain criteria are met based on vehicle operations and a user-selected transmission mode. The governor, when engaged, reduces a throttle command in order limit engine and/or ground speed.

A turbocharger control system of a vehicle includes a trigger module that generates a trigger signal when a transmission of the vehicle is in one of (i) park and (ii) neutral. A wastegate target module, in response to the generation of the trigger signal, sets a target opening of a turbocharger wastegate to a predetermined opening and independently of a position of an accelerator pedal. The predetermined opening is greater than zero percent opening of the turbocharger wastegate. A wastegate actuator module actuates the turbocharger wastegate based on the target opening of the turbocharger wastegate.

In one aspect, a skip fire engine controller is described. The skip fire engine controller includes a skip fire module arranged to determine an operational firing fraction and associated cylinder load for delivering a desired engine output. The skip fire engine controller also includes a firing controller arranged to direct firings in a skip fire manner that delivers the selected operational firing fraction. Various methods, modules, lookup tables and arrangements related to the selection of a suitable operational firing fraction are also described.

A method of controlling a transmission includes determining if an internal combustion engine of the vehicle is currently operating with active fuel management, or if the internal combustion engine is currently operating without active fuel management. The vehicle controller further determines if a possible engine torque is equal to, greater than, or less than a required engine torque. The transmission is upshifted when the internal combustion engine is currently operating with active fuel management, and when the possible engine torque is equal to or greater than the required engine torque. When the possible engine torque is less than the required engine torque, active fuel management is exited so that the internal combustion engine is currently operating without active fuel management. When the internal combustion engine is currently operating without active fuel management, the vehicle controller upshifts the transmission from the current gear ratio to the higher gear ratio.

A method for engine combustion noise feedback control includes calculating an engine combustion noise target value by a controller. A cylinder pressure is measured after combustion of fuel according to a main injection timing and an amount of pilot fuel based on the calculated engine combustion noise target value. A combustion noise index (CNI) is calculated by converting the measured cylinder pressure into a cylinder pressure level. The feedback pilot injection is controlled in which the CNI is applied to injection variable control while controlling the main injection timing and the amount of pilot fuel.