Brake pedal get mushy and goes to the floor if not pumped

Welcome to 2CarPros.

If the pedal goes to the floor, either there is a leak at one of the wheels, one of the brake lines / hoses, or the master cylinder is bad. What happens is when they get older, the plungers in the system get hard and fluid can bypass them. The result is what you described. Now, try this. Pump the brake so you get a good pedal. Hold steady pressure on the brake pedal. Wait a few to see if it starts slowly going to the floor. If it does, my first suspect is the master cylinder. Most times, you won't see a leak with this condition because either the fluid doesn't leak at all or it will sometimes go into the brake booster. This really doesn't sound like a vacuum issue.

Take a look through this link:

https://www.2carpros.com/articles/brake-pedal-goes-to-the-floor

I really feel that is the problem. If you determine it is, here is a link that explains in general how to replace a master cylinder.

https://www.2carpros.com/articles/how-to-replace-a-brake-master-cylinder

Here are the directions specific to your vehicle. The attached picture correlates with the directions.

_______________________

MASTER CYLINDER REPLACEMENT
Master Cylinder Replacement

Removal Procedure

see pic 1

1. Disconnect the electrical connector from the brake fluid level sensor.
2. Disconnect the brake pipes from the master cylinder.

Important: Install a rubber cap or plug to the exposed brake pipe fitting ends in order to prevent brake fluid loss and contamination.

3. Plug the open brake pipe ends.
4. Remove master cylinder mounting nuts.
5. Remove the master cylinder from the vehicle.
6. Drain the master cylinder reservoir of all brake fluid.

Installation Procedure

see pic 1

1. Bench bleed the master cylinder.
2. Install the master cylinder to the vacuum brake booster.

Notice: Refer to Fastener Notice in Service Precautions.

3. Install the master cylinder mounting nuts.
Tighten the master cylinder mounting nuts to 25 Nm (18 ft. lbs.).
4. Remove the plugs from the brake pipes
5. Connect the brake pipes to the master cylinder.
Tighten the brake pipe fittings at the master cylinder to 15 Nm (11 ft. lbs.).
6. Connect the electrical connector to the brake fluid level sensor.
7. Bleed the brake system.

++++++++++++++++++++++++++++++++++++

The link I attached regarding replacement includes directions for bench bleeding the new master cylinder and the brake system. If you need help or have other questions, let me know.

Let me know if this helps.

Take care,
Joe

Good afternoon,

This does sound like a master cylinder.

https://www.2carpros.com/articles/how-to-replace-a-brake-master-cylinder

https://www.2carpros.com/articles/brake-pedal-goes-to-the-floor

https://www.2carpros.com/articles/how-to-bleed-or-flush-a-car-brake-system

When this is done and you get a pedal, take it to a professional to have the work verified. You should only let a professional do brake work. Safety is number 1 concern. I know a lot has to do with economics but only let professional perform this important task.

Roy

You are welcome.

Always glad to help.

Keep us updated.

Roy

Thank you.

Front brakes reprogrammed? No such thing.

What did he do?

Glad to hear it is fixed.

Roy

Hello,

This could be a problem with your vehicle's brake booster check valve or a leak on the vacuum line going to the brake booster. Have an assistant press on the brake pedal and listen to the brake booster vacuum line and check valve for any audible leaks and then get back to us with what you are able to find out.

Thanks,
Alex
2CarPros

These were your words. The front brakes need to be programmed with a brake scan tool.

The scan tool opens the ABS valves for bleeding the system. It is not the programming of any sort.

Roy

Did you have ABS codes stored?

Roy

It could be a bad caliper or rubber brake hose. The hoses sometimes break down inside and won't let fluid run back to the master cylender. As a result, the caliper sticks.