☰
GET A QUOTE

Q: Brake pedal slowly becomes firm to press after short period of driving

asked by on October 18, 2016

I had an issue with one of my rear rotors / pads, so I replaced both rear pads and rotors. I plan to do the front ones tomorrow, but i'm having an issue with the pressure building up in the brake system. The brake pedal gets firm / hard to press down after maybe 5-10 minutes of driving. When this happens it feels like the brakes are constantly being applied, and I will have to press the pedal down pretty hard to be able to shift into reverse. If the car sits parked for awhile the pressure slowly goes back to normal. My initial research tells me that this could be due to a bad / damaged flex hose. Not sure if bleeding the lines / air in the system could possibly cause too much pressure as opposed to too little. I will bleed the system when i'm doing the front brakes tomorrow anyways, but just looking for some input with this problem.

My car has 116000 miles.
My car has an automatic transmission.

Recommended Services

Brake System Inspection $94.99 - $114.99 Get a Quote
Or For Any Other Auto Repairs Get a Quote

Hello and thank you for your question.
The problem lies within the proportioning valve in the brake system. The valve could be plugged up with debris in the system making the valve stick. If the proportioning valve is okay and working correctly, then the brake controller plungers has some debris in the system. I suggest getting two large bottles of brake fluid Dot 3 and flushing out the entire system with all new brake fluid. This will help remove any debris in the system and help keep the system clean. If the system is still being pressurized after flushing out the entire brake system, then you may have to replace the proportioning valve or brake controller to keep the system from building up. If you need assistance with diagnosing your brake system, then seek out a professional, preferably a professional from Your Mechanic to help you with your brake system.

Hyundai
Elantra
2007
L4-2.0L
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing


Experienced Mechanic?

Earn up to $70/hr

What others are asking

1999 Cadillac Escalade cranking, but not starting
Hello. There are a lot of possible causes of this. The most common being a bad fuel pump or crank position sensor. Both are very common. I typically start by checking the computer for codes with a scan tool and...
Read more
Can't start car due to security system
Hi there. Your vehicle's anti-theft system seems to be malfunctioning. A change of ignition cylinder will cause this problem because your vehicle thinks someone attempted to steal it. It is possible to bypass this anti-theft system in order to ensure...
Read more
No crank issue
Hello. Most of the time when you get a cam code on this engine it is because of a crank sensor issue (https://www.yourmechanic.com/article/symptoms-of-a-bad-or-failing-crankshaft-position-sensor). I would replace the crank sensor first. If the problem persists then the timing chain (https://www.yourmechanic.com/article/symptoms-of-a-bad-or-failing-timing-chain) will...
Read more
maybe a wheel bearing worn out, how dangerous is it?
Thanks for your question. If it's a wheel bearing, the noise generally doesn't go away with speed although it might appear that way because the noise gets masked by other noises such as road noise, wind and exhaust. It is...
Read more
Starts off fine and runs, but when I stop if I'm not holding the gas down it cuts off and the battery dies
Hello, thanks for writing in. The issues you are describing can be caused by a few things. A few common causes for stalling are issues with the fuel, ignition, or engine management systems. If any of the components to these...
Read more
Car starts fine sometimes but idles out after pressing the gas.
Hi and thanks for contacting YourMechanic. If you start your engine and it runs fine, then when pushing on the gas pedal then engine starts to rev up and then goes to an idle, this is an issue with the...
Read more
2015 hyundai sanota engine replacement wont start.
Hi there: Yes, in most cases when you replace the OEM engine from any newer vehicle, you have to reprogram the ECU to communicate with the new engine. This is typically only done at a dealership these days.
Read more
No start
If Diagnostic Trouble Codes were downloaded, those codes would really would be key to advising you. If there is no spark, obviously all ignition system components are possible suspects but if the coil(s) and spark plugs are new, the crankshaft...
Read more
What do i do if i put brake fluid in the power steering?
The fluids are incompatible and brake fluid could damage the pump and rack. If you haven't driven the car yet, or even turned it on, drain the reservoir by removing one of the lines from the bottom. Thoroughly and repeatedly...
Read more

Related articles

A Buyer’s Guide to the 2012 Hyundai Accent
Hyundai Hyundai has become a force to be reckoned with in the automobile industry, as they have been improving many different elements of their vehicles – under the hood and with the exterior styling. The 2012 Hyundai Accent is proof...
Read more
A Buyer’s Guide to the 2012 Hyundai Santa Fe
Over Over the years, the Hyundai Santa Fe has really started to come into its own as an SUV. The vehicles have always been affordable, and the same holds true with the 2012 model. Key Features The vehicle offers bucket...
Read more
The Best Used Cars to Buy for College Students
You’ve You’ve done it – high school is officially behind you. Now it’s time to head off to a brand new world. College is that and more and you may need a car during your pursuit of a higher education....
Read more

Browse other content

Cities
Services
Maintenance
Estimates