The present invention provides a cooling device for an internal combustion engine of a vehicle. While the vehicle is in a decelerating state and while the internal combustion engine is in an idle reduction state, the cooling device increases the ratio of the cooling water circulation rate through a first path which extends through a heater core and a radiator while reducing the ratio of the cooling water circulation rate through a second path which bypasses the heater core and radiator. In addition, the cooling device increases the discharge flow rate of the electric water pump while the vehicle is in a decelerating state, and maintains the electric water pump in an operating state during idle reduction. Thus, the present invention allows accelerating the temperature decrease of the cylinder head during idle reduction, as well as improving fuel economy during acceleration when the vehicle is started.

Provided is a work vehicle with which crane work maintenance can be carried out efficiently. Device information relating to a work device that performs prescribed work is detected, and it is determined whether or not the device information indicates a management operation state in which a management operation, which is carried out such that an operation corresponding to the prescribed work is performed, is being carried out. When the management operation state is determined to be in effect, engine stopping is restricted even if an engine stopping condition is net.

Provided are a work machine and engine stopping control device that make it possible to efficiently perform a setting operation related to crane work. When performing prescribed work, the work mode of a work device can be set, and it is determined whether or not the work device is in a setting state in which this work mode is being set. Due to this, when the work device is determined to be in the setting state, stopping of the engine is restricted even if an idling stop permission condition is met.

Variator (20) and forward clutch (Fwd/C) disposed in series are provided between engine (1) having starter motor (15) and driving wheel (7). Sailing stop control that, on the basis of satisfaction of sailing entering condition, interrupts power transmission by frictional engagement element (Fwd/C), stops engine (1) and performs coast-travel is performed. When sailing entering condition is satisfied, coast-travel is started with rotation stop timing of variator (20) being delayed with respect to rotation stop timing of engine (1). When accelerator pedal depression operation intervenes after start of coast-travel, engine (1) is restarted by starter motor (15). When judged that input and output rotation speeds of frictional engagement element (Fwd/C) become synchronization rotation speed after restart of engine (1), frictional engagement element (Fwd/C) is reengaged. Shift response from coast-travel to normal travel is therefore improved at change-of-mind at which sailing quitting condition is satisfied during progress of automatic stop of engine.

Methods and systems are provided for determining a type of spark plug fouling. In one example, a method may include differentiating spark plug fouling due to soot accumulation from spark plug fouling due to fuel additive accumulation based on a current on a control wire of the spark plug following application of a dwell command. Further, exhaust oxygen sensor degradation and/or exhaust catalyst degradation may be determined based on switching frequencies of one or more exhaust oxygen sensors and the type of spark plug fouling.

An engine control method includes determining an intention of a driver for acceleration during vehicle traveling, stopping fuel supply to an engine when a determination is made that the driver does not have the intention for acceleration, detecting a speed of the vehicle during inertial traveling, with fuel supply to the engine kept stopped, permitting restart of the engine when a determination is made that the driver has the intention for acceleration after stopping the fuel supply to the engine, prohibiting the restart of the engine until an engine rotational speed drops to or below a predetermined rotational speed threshold, even when the restart of the engine is permitted, restarting the engine after the engine rotational speed drops to or below the predetermined rotational speed threshold, and changing the rotational speed threshold depending on the detected speed. The rotational speed threshold increases with increase in the detected speed.

In one aspect, a method is described. An operational engine torque is calculated. The engine is operated in a skip fire manner to deliver the operational engine torque. A reference engine torque is calculated using a torque model. The torque model involves estimating torque at a working chamber level. The reference engine torque is compared to the calculated operational engine torque to assess the accuracy of the operational engine torque calculation. Various embodiments of the present invention involve software, devices, systems and engine controllers that are related to one or more of the above operations.

In one aspect, a method is described. An operational engine torque is calculated. The engine is operated in a skip fire manner to deliver the operational engine torque. A reference engine torque is calculated using a torque model. The torque model involves estimating torque at a working chamber level. The reference engine torque is compared to the calculated operational engine torque to assess the accuracy of the operational engine torque calculation. Various embodiments of the present invention involve software, devices, systems and engine controllers that are related to one or more of the above operations.

Methods and systems are provided for increasing airflow through a charge air cooler (CAC) in order to purge condensate from the CAC. In one example, a method includes increasing airflow through the CAC while maintaining torque by selectively deactivating one or more engine cylinders and increasing boost. The number of deactivated cylinders may be based on an amount of condensate within the CAC.

Methods and systems are provided for increasing airflow through a charge air cooler (CAC) in order to purge condensate from the CAC. In one example, a method includes increasing airflow through the CAC while maintaining torque by selectively deactivating one or more engine cylinders and increasing boost. The number of deactivated cylinders may be based on an amount of condensate within the CAC.