Be grateful that your Acura-TL has a vacuum-brake booster nestled between the brake master cylinder and firewall on your Acura. Your vacuum-brake booster doesn't make any noise, and it doesn't use any electricity or gasoline. The Acura TL power Brake Booster ensures that you can stop your car with only a light touch of the brake pedal. Things weren't always like that, before the invention of the vacuum-brake booster, cars still stopped. It's just that you had to really stomp on the brake pedal. The modern Acura TL power vacuum-brake booster is an \ingenious device that operates using something that your engine generates whenever it's running, vacuum. The power vacuum-brake booster takes engine vacuum via a rubber hose that runs from the intake manifold, and theAcura TL  vacuum-brake booster uses that vacuum to amplify the pressure you put on the pedal. A light application of the brakes is translated by the vacuum-brake booster into significantly more pressure on the brake master cylinder, ensuring that your Acura stops quickly.

So what happens to the Acura TL vacuum-brake booster if your car stalls, resulting in a loss of engine vacuum. Early designers realized that gas engines were hardly foolproof, so they designed a little check valve into the vacuum-brake booster circuit. The vacuum-brake booster stores enough vacuum to provide full boost for two or three pedal applications even after the engine dies. The check valve on the vacuum-brake booster is what keeps that vacuum from leaking out. And speaking of leaks, that's the reason most power vacuum-brake booster units have to be replaced. As your vacuum-brake booster ages, the rubber seals and diaphragms that hold the vacuum tend to wear out and crack. If the Acura TL vacuum-brake booster can't hold vacuum (despite the check valve's best efforts), its time is up and you'll need a new or re-manufactured power vacuum-brake booster. When your driving and it seems like you have to push harder on your pedal then you have a problem with either a busted hose or the vacuum-brake booster inside seals are leaking. The Acura TL  vacuum leak ,most of the time doesn't make your engine sound any different. If a hose is busted,  most of the time your engine will sound different. Some vacuum-brake boosters are easy to change, but there is always that one or more that takes a mechanic with special tools to get the brake booster changed.

• Check valve on the vacuum-brake booster is what keeps that vacuum from leaking out.
• Rubber seals and diaphragms that hold the vacuum tend to wear out and crack.
• Some vacuum-brake boosters are easy to change .
• The Acura TL power Brake Booster ensures that you can stop your car.