• Sign Up! To view all forums and unlock additional cool features

    Welcome to the #1 Fiesta ST Forum and Fiesta ST community dedicated to Fiesta ST owners and enthusiasts. Register for an account, it's free and it's easy, so don't hesitate to join the Fiesta ST Forum today!


Brake job mistake

OP
boombots
Messages
295
Likes
42
Location
Charlotte
Thread Starter #41
I saw its held in, but I was more so wondering how it had so much force. I'm sure something else is causing this issue not a master. Maybe an abs fault without a light or a faulty caliper that isn't showing a leak I can see. Maybe one of the boots on the piston is holding the fluid from my sight?

Sent from my XT1064 using Tapatalk
 


OP
boombots
Messages
295
Likes
42
Location
Charlotte
Thread Starter #42
Also, anyone know the size/pitch for the ports on the MC. Advance and AutoZone don't carry whatever size it is. Id like to isolate the front and rear brakes and do some tests that way.

Sent from my XT1064 using Tapatalk
 


D1JL

7000 Post Club
Staff Member
Premium Account
U.S. Navy Veteran
Messages
7,822
Likes
4,060
Location
SFV, So.Cal.
#43
There is nothing in the calipers that can force fluid back with the pressure you are describing.
The caliper dust boot also cannot hold fluid under any kind of pressure.

By bleeding the master, I was only trying to rule that out as a problem.

It is my belief that your problem is in the ABS/HCU module.
The possibility of a valve stuck open and in a bypass position.
The problem I have with this is that I have never seen an ABS/HCU failure without setting a code/light.

My only thought at this point would be to first make sure you have fluid flow from both sides of the master into the ABS/HCU module.
Next disconnect the electronic plug from the module.
Start the car (to provide pressure assistance) and slowly pump the brake pedal.
Yes this should set a code/light but hopefully force the valves back into the correct positions.

If the pedal feels somewhat normal then bleed the brakes again.
If bleeding seems normal, have someone hold the pedal down and check to see if the wheels lock up.

Lastly reconnect the plug on the ABS/HCU module and restart the car.
The system should go through the self test procedure.

Any codes or lights that may have been set will not go away until the car is driven (without an ABS reset tool).

If things don't feel correct or normal, tow it to a dealer.



Good Luck,
Dave
 


OP
boombots
Messages
295
Likes
42
Location
Charlotte
Thread Starter #44
I am hesitant to unhook lines at the abs module as I don't want to introduce air into it. I tried the unplugging and it did nothing different when unhooked (besides lights on the dash) and changed nothing after restarting with it plugged in. I checked the rear brakes to see if the pads were seated right and they are... I did notice my parking brake seems lighter to pull but it still has enough grab to stop my car from driving when I let the clutch out...

I just have this feeling Ford is going to screw me hard and try to do another new master, or say the rotors and pads aren't oem so that's is causing the issue. I'm out of options and patience so I guess I'll see what they say...

Sent from my XT1064 using Tapatalk
 


D1JL

7000 Post Club
Staff Member
Premium Account
U.S. Navy Veteran
Messages
7,822
Likes
4,060
Location
SFV, So.Cal.
#45
I am hesitant to unhook lines at the abs module as I don't want to introduce air into it.

You already disconnected the lines at the master so air has already gotten in.
There would be no difference disconnecting at the other end of the same line.

You have stated that when last you bled the system, you got no fluid at the front calipers.
You also say that you don't want to be screwed and sold another master but you don't want to prove that the master is working.
Electrically unplugging the ABS/HCU module SHOULD have done nothing if the master is not working.

I do agree with you about getting screwed.
However if I was still doing this professionally and working on this car.
I would replace everything just because you worked on it first.
Mainly because I would not wish to be responsible for something that someone else may have screwed up.
One thing I never took lightly was repairing brake systems.




Dave
 


OP
boombots
Messages
295
Likes
42
Location
Charlotte
Thread Starter #46
You're right. It makes sense. Brake troubleshooting is definitely not my wheelhouse. I do enjoy turning wrenches but I'm just wore out with work and frustrated. I'm looking forward pulling the motor in my truck this winter though. Thank you for talking me through this.

Could I plug one port on the master to isolate the front from the rear brakes for further troubleshooting after doing your recommendation? With that said can I use a bolt as a plug? Noone has plugs/fittings this size and pitch.

Sent from my XT1064 using Tapatalk
 


Intuit

3000 Post Club
Messages
3,601
Likes
2,203
Location
South West Ohio
#47
As an alternate means of isolating, you may be able to buy a short piece of copper line, squeeze and seal off the end with a torch and solder, then attach to the master.
 


D1JL

7000 Post Club
Staff Member
Premium Account
U.S. Navy Veteran
Messages
7,822
Likes
4,060
Location
SFV, So.Cal.
#48
From what you have said, it appears that the rear brake portion of the master works.
The front brake portion should be the rear half of the master.
To avoid buying anything, if you disconnect the line at the ABS module, you could then place a clear plastic hose on it then into a bottle and bleed the master.
Use a pair of plyers to crimp the plastic hose to prevent air from going back to the master.
Although I do not know the size and thread, the fittings are standard items and should be available at most auto parts stores, I do believe they are metric however.

You could also just remove the line from the master and hold your finger over the port.
Then pressing the pedal, you should be able to feel the fluid pressure.



Dave
 


OP
boombots
Messages
295
Likes
42
Location
Charlotte
Thread Starter #49
May seem like it's taking me forever to solve this... I have a second vehicle for anyone wondering. Hoping to have some time this evening to tinker again.

Sent from my XT1064 using Tapatalk
 


OP
boombots
Messages
295
Likes
42
Location
Charlotte
Thread Starter #50
Pressure at both ports on the master. Tried to bleed again, no luck. I am simply out of time. My truck has some issues that need addressed and continuing to d.d. it is not wise at this point. I had the FiST towed to ford. The tow truck driver loved it and was checking it out. He is a 300zx guy.

Thank you for those who helped me out. I'll update with results and how bad they screw me price wise...

Sent from my XT1064 using Tapatalk
 


OP
boombots
Messages
295
Likes
42
Location
Charlotte
Thread Starter #51
Update... Ford said they fixed it and said air in system that required special tools or whatever... Got in the car and drove off. Went to stop and brakes went to the floor and almost rearended someone. Needless to say not happy they didn't test drive the car and just sent me off and charged me for it... So I'm back here as the mechanic test drives the car. He basically said I'm full of shit about the brakes not working as he said the pressure checked it...

Sent from my XT1064 using Tapatalk
 


OP
boombots
Messages
295
Likes
42
Location
Charlotte
Thread Starter #52
And I was basically told take it home we don't want to fix it. They said absolutely no air and they cant do abs system cycle on this model. They said they'd put factory pads and rotors on. He said try to put different pads on the car, as in go to Napa and buy different pads.

I don't see how these pads and rotors would do this at all but I'll try. Wish I had the stock shit still to prove a point...

Sent from my XT1064 using Tapatalk
 


CanadianGuy

4000 Post Club
Messages
4,097
Likes
942
Location
Southern Ontario
#53
Could it be a pedal position issue where the pedal sinks further to engage the system and the system is fine? Seen that before on an old blazer.
 


OP
boombots
Messages
295
Likes
42
Location
Charlotte
Thread Starter #54
Could that happen after a standard brake job? I know I pulled the booster and could have knocked something out there but it happened before that too. Also didn't see any adjustment for the pedal either.

Sent from my XT1064 using Tapatalk
 


CanadianGuy

4000 Post Club
Messages
4,097
Likes
942
Location
Southern Ontario
#55
Could that happen after a standard brake job? I know I pulled the booster and could have knocked something out there but it happened before that too. Also didn't see any adjustment for the pedal either.

Sent from my XT1064 using Tapatalk
I'm going by the assumption that the mechanic for check pressure and fixed the previous issue. Only thing left is the abs module from what I read. But maybe Dave can shed some light.
 


OP
boombots
Messages
295
Likes
42
Location
Charlotte
Thread Starter #56
He said they can't cycle the module on an st, but can on other cars. I smell bs there.

Sent from my XT1064 using Tapatalk
 


LilPartyBox

1000 Post Club
Premium Account
Messages
1,470
Likes
755
Location
NYC
#57
that sounds like pure bs. ur supposed to believe Ford built a car without fully serviceable brakes. and even if that's remotely true, why not replace the abs module? since, u know, it can't be cycled.
 


D1JL

7000 Post Club
Staff Member
Premium Account
U.S. Navy Veteran
Messages
7,822
Likes
4,060
Location
SFV, So.Cal.
#58
As I suspected all along, your problem is in the ABS/HCU.
By forcing fluid back up stream into the system you must have jammed a valve.
I believe the Master Cylinder Isolation Valve.

The problem I have with is that you say there NO brake failure lights as I have never seen a failure like this without a light/code.
The tech at the dealer should check for codes with an ABS scan tool anyway.

Here is what the Fiesta service manual says (covers STs as well).

Using a diagnostic scan tool, CARRY OUT the Inlet Valve Calibration routine and then the Master Cylinder Isolation Calibration routine.
CLEAR the DTC and REPEAT the self-test. If the DTC returns, REPEAT both calibration routines making sure to FOLLOW the diagnostic scan tool directions.
CLEAR the DTC and REPEAT the self-test. If the DTC returns, INSTALL a new ABS module and HCU assembly.


You may have an additional problem of the Instrument cluster not reporting a problem.

You should do a instrument cluster light test.


Assuming you take it back to the dealer to recheck the ABS module.
You should allow them to install new pads and rotors.
When they return your car to you, make sure the tech and your service writer note on your work order that there was no other problem found.

On your way off of their lot, RUN INTO ONE OF THEIR NEW CARS.
Then see what they say.



Dave
 


OP
boombots
Messages
295
Likes
42
Location
Charlotte
Thread Starter #59
I also agree with the abs issue. I regret not hitting a car, and wish they would have on the test drive... I'm going to call another dealer and talk to their tech about the abs mod.

Sent from my XT1064 using Tapatalk
 


Intuit

3000 Post Club
Messages
3,601
Likes
2,203
Location
South West Ohio
#60
I have an idea... a code/light should automatically be set whenever brake pedal travel is excessive... outside of normal parameters.

To help minimize cost while potentially maximizing transferability and serviceability, I'd make use of a small, cheap optical sensor, possibly infrared, to measure closing distance from a point that is near the fulcrum. The failsafe is the fact that a dirty or inoperable sensor would set the code. The sensor should be able to operate under moderate soot/dust conditions without tripping. A reflective surface may increase MTBF. A rare cleaning may still prove necessary.
 


Similar threads



Top