Skip the auto shop - Our mechanics make house calls

Q: Brakes intermitently mushy

asked by on

The past few months, my brake pedal has been going to the floor randomly while braking. It doesn't always happen. I was recently in the car roaming around for a quarter hour, stopping often, and I couldn't make it happen. The fluid level looks fine. Today, it happened several times. After it had sat for a while, it felt like the brake pedal was mushy when I first put on the brakes. I drove it around. Of course, the problem disappeared. What's going on? If my master cylinder is going bad, would it be intermittent like this?

A: Hello. It sounds like there could be an int...

Hello. It sounds like there could be an intermittent master cylinder condition.

The master cylinder acts as a pump for the brake system. In the master cylinder, the valves or diaphragm could get stuck, collapse, or not open properly, causing an intermittent problem. It is also possible that complete failure of the master cylinder has occurred.

Have a certified technician, like one from YourMechanic, come out to diagnose your issue and replace the master cylinder.

Was this answer helpful?

Need advice from certified mechanic? Get help now!

Over 1000 mechanics are ready to answer your question.
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Ask a Mechanic
(100% Free)

Have a car question? Get free advice from our top-rated mechanics.

Ask A Mechanic
Over 10,000 questions answered!

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Save up to 30%

Get a quote

What others are asking

Q: Feels like emergency brake is engaged after driving 60 miles and acceleration is more difficult, plus metallic scraping noise

It could be that the calipers are sticking, there is a problem in the hydraulic system or the brake brake cable is seized. Any of these issues could cause your brakes to be applied all of the time, potentially resulting...

Q: How to replace the timing belt and camshaft

Ideally, you should have aligned the marks before you removed the timing belt. It sounds as though everything is completely disassembled already. This makes things a bit more difficult. I would only recommend assembling it the same way as you...

Q: C4500; 6.6 2007 diesel shut down while driving, turns over but won't start

Hello there, thank you for asking about your Chevrolet truck. There are a variety of things that could cause this as the Duramax diesel trucks have over 20 onboard computers. Without additional information as to trouble codes or other symptoms...

Related articles

What Causes Hoses to Leak?
While the largest part of your engine is mechanical, hydraulics plays a significant role. You’ll find fluids at work in a number of different areas. Your car's fluids include: Engine oil Transmission...
How to Renew Your Car Registration in Oklahoma(DELETED)
Having your car registered with the Oklahoma Tax Commission is an important part of driving legally in this state. You will need to do this within 30 days of moving to Oklahoma...
P0052 OBD-II Trouble Code: HO2S Heater Control Circuit High (Bank 2 Sensor 1)
P0052 code definition HO2S Heater Control Circuit High (Bank 2 Sensor 1) What the P0052 code means This code is seen when the Engine Control Module (ECM) tries to control the...