Q: Engine stalls when the brakes are applied

Hello. From what you describe it would appear that your vehicle may be experiencing possible engine management or transmission issues. The symptoms you describe can commonly be caused by faulty idle air control valve. The idle air control valve is the component that maintains and adjusts the vehicle’s idle speeds. It is controlled by the engine computer, which calculates the proper idle speed using inputs from the various engine sensors. If there is an issue with idle air control valve, or with the inputs it gets its direction from then the engine could experience issues such as irregular idle and stalling. The same can also be caused by a vacuum leak or issues with the brake booster. It may also be possible that you are experiencing transmission issues. The transmission uses a series of electrical sensors and solenoids to control the transmission’s shifting. If any of these solenoids or sensors develop an issue they can cause all sorts of transmission and performance related problems, including stalling and late shifting. If the check engine light is on, retrieving the trouble codes may shed some light on what the issue could be. As these sorts of problems can sometimes be difficult to diagnose, I would recommend having a professional technician, such as one from YourMechanic, come to your location to diagnose what may be causing your vehicle’s stalling and performance issues.