Brakes locked up

[Chiro6262]

Brakes were soft and spongy so we proceeded to bleed the brakes. After it was complete, one push of the pedal completely locked up all four wheels. Now they won’t release. Any ideas on why this would happen? I re-bled them and the same thing happens. What am I doing wrong? No brake shop or dealer will touch it because it’s a modified rally car.

 

[M-Sport fan]

Take it to Dirtfish.

But it sounds like a master cylinder problem.

Did you remove the ABS system for rally use purposes?

 

[RubenZZZ]

Does it run a booster?

Sometimes the master cylinder leaks fluid inside the booster. The fluid builds up and will cause the brakes to engage and stayed locked. Common problem on mid 2000s GM vehicles.

Sent from my 2PYB2 using Tapatalk

 

[Chiro6262]

Disabled the abs by pulling wheel sensor when rallying. This car went upside down at the Ojibwe rally. Brakes worked fine rolling it around the driveway but we’re a little soft so we bled them. Ever since then they’ve been locked up.

 

[Chiro6262]

The thing that bugs me is they were just a little soft before bleeding (engaged and released just fine). Bled brakes, finished, applied brakes and locks up all four.

 

[M-Sport fan]

Disabled the abs by pulling wheel sensor when rallying. This car went upside down at the Ojibwe rally. Brakes worked fine rolling it around the driveway but we’re a little soft so we bled them. Ever since then they’ve been locked up.

Are you the Magnetic Gray L2WD class FiST, running on Sparco Terra wheels/Hoosier gravels, that was at NEFR, from the northwest?
(If so, I spoke to you before that rally, in the main service park on that Thursday.)

I am guessing that you already carefully checked the hard lines under the unibody to make sure they did not get kinked/bent in the roll?

 

[Chiro6262]

Yes. All was good (other than a little soft) u til we bled the brakes. And yes we’re the Grey ST from Washington. My son Chase is the driver. Trying to get this solved to run in Olympia this weekend.

 

[Sekred]

If you crack all the bleed screws do the brakes unlock?

 

[D1JL]

If is not the master Cylinder then you may have a ball valve stuck in the ABS module.
You could try to free it up by first opening the bleeders then tap on the ABS module.

What I don't understand is why you don't want ABS?
It is the only good automated system in cars.
I love it on the track.



Dave

 

[Chiro6262]

Yes I’d i crack open bleeders the wheel releases. BUT immediately seize up again when I apply brakes with bleeder closed.

 

[Sekred]

Yes I’d i crack open bleeders the wheel releases. BUT immediately seize up again when I apply brakes with bleeder closed.

Ok, what Dave said but with the brakes locked on, try cracking the lines at the MC and see if there is any pressure build up there and if the brakes release otherwise it sounds like the ABS unit.

 

[D1JL]

Ok, what Dave said but with the brakes locked on, try cracking the lines at the MC and see if there is any pressure build up there and if the brakes release otherwise it sounds like the ABS unit.

Correct.
That sounds better then the way I said it


Dave

 

[Chiro6262]

Yes it has a booster. I’m thinking it has to be an abs fail rather than MC. It worked as it should before the bleed. Any ideas on a code reader that cycles the ABS?

 

[D1JL]

My Snap-on does ABS.
But I don't think the inexpensive ones do.


Dave

 

[ThaiFiesta]

Yes it has a booster. I’m thinking it has to be an abs fail rather than MC. It worked as it should before the bleed. Any ideas on a code reader that cycles the ABS?

Forscan has a ABS module in Beta version.

 

[Questionable]

Hey, I just dealt with the same issue, but I haven't disabled the ABS. Did a pad swap and flush and then all the brakes locked up and the car wouldn't move.

Check your brake pedal and see if you can pull it "up" toward you. I still don't know what actually happened to cause my issue, but the tech adjusted the pedal trying to diagnose the brake problem and the issue went away. It might not be the problem, but hey it's free to check and you won't have to buy a B-Spec ABS system like I did.

 

[Quisp]

Hey, I just dealt with the same issue, but I haven't disabled the ABS. Did a pad swap and flush and then all the brakes locked up and the car wouldn't move.

Check your brake pedal and see if you can pull it "up" toward you. I still don't know what actually happened to cause my issue, but the tech adjusted the pedal trying to diagnose the brake problem and the issue went away. It might not be the problem, but hey it's free to check and you won't have to buy a B-Spec ABS system like I did.

Maybe this clears the return port in the M/C ?

 

[Chiro6262]

Fiesta Brakes Fixed

Thanks for all the help. Son of a B*tch if pulling up on the brake pedal fixed it! What a pain in the ass.

Maybe this clears the return port in the M/C ?

 

[Questionable]

Thanks for all the help. Son of a B*tch if pulling up on the brake pedal fixed it! What a pain in the ass.

So that was the issue? I ended up with a return spring on my brake pedal because the issue kept coming up when bleeding the brakes.

That solution works, but it feels like it fixes a symptom not a cause.

 

[LaserWhisperer]

Not Fiesta related, but my wife's Camry does this from time to time. I just lift the pedal with my toe and it works fine