After driving for about five miles the brakes harden up vehicle loses acceleration?

2008 FORD ESCAPE

160,000 MILES • 4 CYL • 2WD • AUTOMATIC

MATTCOOPER005

MEMBER
2 POSTS

Hello,

The vehicle listed above runs like a champ for about 5 miles, then the brakes harden up to the point of just tapping the brake pedal causes the vehicle to come to a quick stop. The vehicle struggles to accelerate as if the brakes are restricting any movement. After stopping, the vehicle stays completely stalled until the gas pedal is floored. Symptoms occur faster and more severely when A/C is on.

I recently replaced the cat and ignition switch.

Please help!

Jul 16, 2023 at 4:32 PM

STRAILER

✓ASE Certified Mechanic
54,840 POSTS

Can you tell if the brakes are hot like they are causing the problem? Or does it feel like the engine has low power which will cause low vacuum and make the brake pedal hard to push. If the brakes are hot it sounds like the brake booster and master cylinder need to be replaced, here is a guide to help with the problem and instructions in the images below to help you with the repair, also I have included a guide to help you test the catalytic converter.

https://www.2carpros.com/articles/a-comprehensive-guide-to-fixing-automotive-brakes-locking-up

and

https://www.2carpros.com/articles/how-to-test-a-catalytic-converter

Check out the images (below). Please let us know how it goes

Images (Click to enlarge)

Professional Diagram for 2CarPros Members
Click here to log in and view diagram.

Jul 17, 2023 at 12:22 PM

MATTCOOPER005

MEMBER
2 POSTS

Thanks Ken! Yes, the brakes seem to be hot, and it almost smells like something is burning. The brake booster was replaced about a year ago so I'll look at the master cylinder next.

Jul 22, 2023 at 8:28 PM

STRAILER

✓ASE Certified Mechanic
54,840 POSTS

Sounds good, also while the master is off check to see if you can adjust the booster push rod inward, some boosters don't have an adjustment. Please let me know what happens.

Jul 24, 2023 at 10:41 AM