A brake pedal on a Chevy.

Problems that can cause a hard brake pedal

In Brakes by HomeTowne Auto Repair & Tire

We do a lot of braking in Northern Virginia, where there are many commuters and traffic is a daily expectation.

For this reason, it’s important to make sure the braking system is working correctly and any abnormal symptoms are addressed.

A hard brake pedal is one problem you should watch out for.

Hard brake pedal causes

There are several possible reasons why a brake pedal is hard to push.

Brake booster not working correctly

The brake booster may not be able to provide vacuum pressure. This can occur if there is a diaphragm tear or a broken check valve. You can confirm the brake booster is the problem by turning off the vehicle and stepping on the brake pedal multiple times. Continue to press it and restart the car. The brake pedal should go down if the brake booster is functioning the way it should. A brake pedal that remains firm is an indicator that the brake booster has gone bad.

Vacuum pump or power steering pump going bad

What’s causing a stiff brake pedal can differ among vehicles and the type of brake booster they have. Some cars use a hydraulic brake booster, where the power steering pump – rather than the engine vacuum – creates pressure. Certain brake boosters use the intake manifold while others have an electrical driven pump or a mechanical driven pump.

A bad electric pump, not having enough power steering fluid, and a missing serpentine belt can result in a hard brake pedal among vehicles with a hydraulic brake booster or vacuum pump.

A vacuum brake booster.
Vacuum brake booster

Vacuum hose becomes cracked

Is the brake pedal hard to push and hisses? The problem could have to do with the vacuum hose, which links the engine and brake booster. A vacuum is made due to air being drawn in. Cracks can form where the vacuum connects with other components.

Electronics associated with the electro hydraulic brake booster: With the brake systems having a lot of electronic controls – such as anti-lock brakes and traction control – that can be integrated with the master cylinder and the brake booster, especially if it’s an electro hydraulic brake booster. For example, Toyota 4Runners have an electro hydraulic brake booster, meaning that there’s an electric pump that will pump up the pressure to the accumulator. That allows you to have easy brake pressure when applying the brakes. But if there’s a problem with the solenoid or module, that could make it so the brake pedal feels hard. In this case, we need to go in and perform diagnostic testing to determine the problem.

An electro hydraulic brake booster.
Electro hydraulic brake booster

Caliper or caliper slides have seized: If the caliper or caliper slides have seized, the caliper isn’t able to move back and forth or the piston isn’t able to move out as you press the brake pedal. That can give you a harder brake pedal feel, but you would notice the car isn’t stopping as well as it used to. Rust and caliper seizing problems are more common among vehicles that are used in areas like Nag’s Head – where you might get a lot of salt air and salt water, and maybe some water coming up on the roads – and New England – where drivers see a lot of salt on the roads.

Note: This may seem silly, but make sure to take a look at the floor when trying to figure out why the brake pedal is hard to push. The floor mat could have become caught underneath the pedal. This used to be a more common problem years ago, but stranger things have happened.

It’s important to take care of your brake system, which can help extends its lifespan. This includes replacing brake pads and rotors and other components, such as brake hoses and brake lines, when needed. We also recommend regular brake fluid exchanges every 30,000 miles.

HomeTowne Auto Repair & Tire is an authorized Michelin and BFGoodrich tire dealer located in Woodbridge, Virginia. Automotive repair services are performed on all makes and models, including oil changes, brakes, alignments, inspections, and computer engine diagnostics.