A brake negative pressure control device for a vehicle includes an ECU. The ECU is configured to (i) control a first fuel injection valve and a second fuel injection valve, when the ECU determines that a negative pressure in a negative pressure chamber is insufficient, such that a ratio of a fuel injection amount by the first fuel injection valve is decreased and a ratio of a fuel injection amount by the second fuel injection valve is increased; and (ii) control an opening degree of the throttle valve, when the ECU determines that the negative pressure in the negative pressure chamber is insufficient, such that the opening degree of the throttle valve at the time when the ECU determines that the negative pressure is insufficient is smaller than an opening degree of the throttle valve at the time when the ECU determines that the negative pressure is not insufficient.

A brake negative pressure control device for a vehicle includes an ECU. The ECU is configured to (i) control a first fuel injection valve and a second fuel injection valve, when the ECU determines that a negative pressure in a negative pressure chamber is insufficient, such that a ratio of a fuel injection amount by the first fuel injection valve is decreased and a ratio of a fuel injection amount by the second fuel injection valve is increased; and (ii) control an opening degree of the throttle valve, when the ECU determines that the negative pressure in the negative pressure chamber is insufficient, such that the opening degree of the throttle valve at the time when the ECU determines that the negative pressure is insufficient is smaller than an opening degree of the throttle valve at the time when the ECU determines that the negative pressure is not insufficient.

Methods and systems are provided for detecting a fault within a brake booster system of a vehicle. In one example, a method may include measuring the pressure of a brake booster chamber and the pressure of an inlet manifold, comparing the booster chamber and inlet manifold pressures, determining the faulty source, and restricting the use of an electrical system in case of a fault. In this way, the pressure within the inlet manifold may be reduced or maintained in the event of a fault.

Methods and systems are provided for detecting a fault within a brake booster system of a vehicle. In one example, a method may include measuring the pressure of a brake booster chamber and the pressure of an inlet manifold, comparing the booster chamber and inlet manifold pressures, determining the faulty source, and restricting the use of an electrical system in case of a fault. In this way, the pressure within the inlet manifold may be reduced or maintained in the event of a fault.

Methods and systems are provided for providing vacuum to a brake booster via an aspirator system. In one example, a system may include an aspirator system fluidly coupled with a brake booster with no intervening components located therebetween.

Methods and systems are provided for providing vacuum to a brake booster via an aspirator system. In one example, a system may include an aspirator system fluidly coupled with a brake booster with no intervening components located therebetween.

A brake actuation recognition device has an evaluation device by which at least one provided modification quantity relating to a temporal change in an actual quantity relating to a pressure in a pressure chamber of a brake booster of a brake system is compared with a specified comparison quantity range such that, if the at least one provided modification quantity is within the comparison value range, it is determined that a brake actuating element situated on the brake system is in an actuation state below a specified minimum actuation state, and a corresponding information is outputted.

A brake actuation recognition device has an evaluation device by which at least one provided modification quantity relating to a temporal change in an actual quantity relating to a pressure in a pressure chamber of a brake booster of a brake system is compared with a specified comparison quantity range such that, if the at least one provided modification quantity is within the comparison value range, it is determined that a brake actuating element situated on the brake system is in an actuation state below a specified minimum actuation state, and a corresponding information is outputted.

Methods for controlling vacuum within a brake booster by modifying powertrain operation include determining an intake manifold vacuum in response to actuation of a brake pedal. Increasing the intake manifold vacuum if the brake booster vacuum is less than a desired brake booster vacuum. In some embodiments, the transmission is downshifted to increase engine speed and intake manifold vacuum.

Methods for controlling vacuum within a brake booster by modifying powertrain operation include determining an intake manifold vacuum in response to actuation of a brake pedal. Increasing the intake manifold vacuum if the brake booster vacuum is less than a desired brake booster vacuum. In some embodiments, the transmission is downshifted to increase engine speed and intake manifold vacuum.