The present invention is equipped with: a valve opening/closing timing control mechanism that sets the opening/closing timing of an exhaust valve; and a lock mechanism that holds the rotation phase of the valve opening/closing timing control mechanism in a first lock phase, in which the open state of the exhaust valve is maintained when the intake valve opens.

A mobile machine control method includes receiving, by a single controller, a first request for movement of the machine by a ground-engaging device, receiving, by the single controller, a second request for movement of an implement system of the machine, and determining, with the single controller, an amount of desired power from an engine to satisfy the first request and the second request. The method also includes selecting an engine speed from a plurality of candidate engine speeds to produce the desired power and operating the engine at the selected engine speed to produce the desired power.

In at least some implementations, an engine control process includes an engine speed test and other steps. The engine speed test includes the steps of a) determining a first engine speed, b) changing the air/fuel ratio of a fuel mixture delivered to the engine, and c) determining a second engine speed after at least some of the air/fuel ratio changing event, Based at least in part on the difference between the first engine speed and the second engine speed it is determined if a change in the air/fuel ratio of the fuel mixture delivered to the engine is needed. If a change to the air/fuel ratio was indicated, the air/fuel ratio of a fuel mixture delivered to the engine is changed.

An on-board vehicle computing system stores values in a memory of a first engine control unit (ECU) and stores corresponding backup values in a memory of a second ECU. In this way, the second ECU provides data backup functionality for the first ECU's data. The system may retrieve a backup value from the first ECU and restore the corresponding value in the second ECU using the backup value. In one illustrative scenario, if an original engine ECU (EECU) fails and a replacement EECU is installed, the system can retrieve backup values for vehicle speed limiter (VSL) parameters from memory in a cab ECU (CECU) and update the corresponding data in the replacement EECU with the backup values.

A control system for an engine of a vehicle includes an adder module that determines a temperature sum based on a sum of a plurality of temperatures determined based on (i) a plurality of operating parameters of the vehicle and (ii) a plurality of predetermined values calibrated for determining an estimated temperature at a location within an exhaust system of the vehicle. A temperature difference module determines a temperature difference based on the temperature sum and a previous value of the temperature difference. An estimating module determines the estimated temperature at the location within the exhaust system based on the temperature difference and a reference temperature. An actuator control module selectively adjusts at least one engine actuator based on the estimated temperature.

A control system for an engine of a vehicle includes an adder module that determines a pressure sum based on a sum of a plurality of pressures determined based on (i) a plurality of operating parameters of the vehicle and (ii) a plurality of predetermined values calibrated for determining an estimated pressure at a location within an exhaust system of the vehicle. An estimating module determines the estimated pressure at the location within the exhaust system based on the pressure sum and a reference pressure. An actuator control module selectively adjusts at least one engine actuator based on the estimated pressure.

A control system for an engine of a vehicle includes an adder module that determines a temperature sum based on a sum of a plurality of temperatures determined based on (i) a plurality of operating parameters of the vehicle and (ii) a plurality of predetermined values calibrated for determining an estimated temperature at a location within an exhaust system of the vehicle. A temperature difference module determines a temperature difference based on the temperature sum and a previous value of the temperature difference. An estimating module determines the estimated temperature at the location within the exhaust system based on the temperature difference and a reference temperature. An actuator control module selectively adjusts at least one engine actuator based on the estimated temperature.

A control system for an engine of a vehicle includes an adder module that determines a pressure sum based on a sum of a plurality of pressures determined based on (i) a plurality of operating parameters of the vehicle and (ii) a plurality of predetermined values calibrated for determining an estimated pressure at a location within an exhaust system of the vehicle. An estimating module determines the estimated pressure at the location within the exhaust system based on the pressure sum and a reference pressure. An actuator control module selectively adjusts at least one engine actuator based on the estimated pressure.

Methods and systems are provided for triggering a humidity measurement based on changes in ambient conditions. In one example, a method may include, in response to a higher than threshold change in ambient air temperature or pressure, operating an oxygen sensor to update an ambient humidity estimate. Engine operation parameters may be adjusted based on the updated ambient humidity estimate.

Methods and systems are provided for mitigating the effects of a leaky fuel injector during vehicle idle stop conditions. In one example, a method may include identifying the cylinder with a leaky fuel injector, and at or during engine shutdown, positioning the engine to a selected position based on the identified cylinder such that an exhaust valve of the identified cylinder is at least partly open.