Q: Why does my car cut off when I hold on the brake

Brakes don’t have any connection that will affect the way your car runs. What is likely happening is the car is idling too low in gear, which is what is happening when you come to a stop. It will only do this once it is warmed up. Most likely you have a problem with your IAC (idle air control) valve. They get gummed up with carbon deposits and stick.

One other possibility is your power brake booster has a vacuum leak. When you press on the brake pedal, it will open the intake manifold to atmospheric pressure allowing un-metered air into the engine. Cars with MAF (mass air flow) sensors don’t do well with vacuum leaks and your car has a MAF. This can easily be tested for by pinching off the hose connected to the brake booster and pressing on the brake pedal. If the car doesn’t die on you, then you have successfully diagnosed your car.

If you’d like to get this fixed, consider YourMechanic, as a certified professional can come to the vehicles location and diagnose the stalling issue firsthand.

Keep in mind, your car should be completely warm when doing this test.

Good luck!