Abstract: An automatic transmission control system causes a downshift to a gear which can provide an effect of engine braking greater than that provided before the downshift when the vehicle falls its speed with a specified rate of speed reduction as a result of footbrake application while the vehicle is traveling on a downgrade having a slope greater than a specified slope.

Abstract: An automatic transmission control system, which applies an ordinary gear shift control map set up for flat road driving and a downgrade gear shift set up for downgrade driving which has broadened range of driving conditions for lower gears, causes gear shifts according to the ordinary gear shift control map even during downward driving when an accelerator pedal is stepped on with intention of accelerating the vehicle.

Abstract: A control system for a multiple cylinder engine includes a vapor fuel introduction system for introducing a vapor fuel vaporized in a fuel tank. A feedback device is used for setting an air fuel ratio feedback compensation value for each of the cylinders or each group of cylinders of the engine and for executing an air fuel ratio feedback control. A fuel supply device is used for supplying engine fuel for each cylinder so as to equalize the air fuel ratio feedback compensation values of each of the cylinders or each group of the cylinders regardless of a change of an operating condition of a vapor fuel introduction control. A desirable A/F feedback control can be accomplished regardless of the execution of the vapor fuel purge in the multiple cylinder engine.

Abstract: A control device for an automotive vehicle comprises a differential disposed between wheels or wheel axles of a vehicle an antiskid brake control device to control an antiskid brake device which is capable of adjusting a brake pressure applied to a brake device of the vehicle to prevent wheels of the vehicle from locking, a differential limiting control device having a differential limiting device being capable of controlling and transferring a differential limit to the differential, and operating to decrease the differential limit while the antiskid brake device is operating, such that when either the antiskid brake control device or said differential control device fails, the non-failing control device receives a failure signal from the failing control device and the non-failing control device controls the vehicle towards a stable condition or increases a brake force.

Abstract: A control device for an automotive vehicle comprises a differential disposed between wheels or wheel axles of a vehicle an antiskid brake control device to control an antiskid brake device which is capable of adjusting a brake pressure applied to a brake device of the vehicle to prevent wheels of the vehicle from locking, a differential limiting control device having a differential limiting device being capable of controlling and transferring a differential limit to the differential, and operating to decrease the differential limit while the antiskid brake device is operating, such that when either the antiskid brake control device or said differential control device fails, the non-failing control device receives a failure signal from the failing control device and the non-failing control device controls the vehicle towards a stable condition or increases a brake force.

Abstract: A differential action control device of a vehicle includes an inter-axle differential disposed between axles for making a differential action between the axles, an inter-wheel differential disposed between wheels for making a differential action between the wheels, and a parameter setting device for detecting a vehicle running condition and setting a predetermined parameter based on the vehicle running condition detected. The device further includes target yaw rate setting device for setting a target yaw rate of the vehicle based on the parameter, a yaw rate detecting device for detecting an actual yaw rate of the vehicle while running, and a differential control device for controlling a differential action of the inter-axle and inter-wheel differentials based on a deviation between the actual and target yaw rate of the vehicle. The steering characteristic of the vehicle can be changed to get a desirable characteristic by making the differential action control.

Abstract: A throttle valve control system calculates a throttle opening of a throttle valve according to a predetermined relationship based on the displacement of an accelerator and regulates an air-fuel ratio at which a fuel mixture is applied to the cylinders. The speed at which the throttle valve is driven is controlled, based on the throttle opening and the air-fuel ratio, so as to be lower when the air-fuel ratio provides a lean fuel mixture than when the air-fuel ratio provides a rich fuel mixture. The throttle valve is finally driven to open to the throttle opening at this speed.