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Discussion Starter · #1 ·
I replaced pads, rotors, and a caliper. Then pedal went straight to the floor. Then I had a shop replace the master cylinder and vacuum bleed. Better, but still waaaay too soft. To the point where it’s barely drivable. Shop says it might be ABS related, but even they aren’t sure. Any ideas?

2006 Spec V, if it matters.
 

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Might be abs related... Pull the fuse for the abs and take it for a ride see if it changes. Probably not. Bad abs is usually not a squishy pedal.

If you drive and press the brake...let off real fast and hit it again is the pedal good then?(pumping the pedal)....if so its probably something like the power boster.
Listen for leaks or spray something around it to check.

If that's not it you'll be moving to a proportioning valve/distribution block.
 

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Did you replace the rubber lines? If you didn't not then you may have the original lines from the factory and they are probably expanding when pressure is applied. There is a reason everyone switches to steel braided lines, last forever and increases pedal feel and stiffness.

I don't have abs so I can't help you there.
 

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Discussion Starter · #4 ·
Did you replace the rubber lines? If you didn't not then you may have the original lines from the factory and they are probably expanding when pressure is applied. There is a reason everyone switches to steel braided lines, last forever and increases pedal feel and stiffness.

I don't have abs so I can't help you there.
Nope I didn't touch the lines, I would assume they are the factory lines.
 

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Discussion Starter · #5 ·
Might be abs related... Pull the fuse for the abs and take it for a ride see if it changes. Probably not. Bad abs is usually not a squishy pedal.

If you drive and press the brake...let off real fast and hit it again is the pedal good then?(pumping the pedal)....if so its probably something like the power boster.
Listen for leaks or spray something around it to check.

If that's not it you'll be moving to a proportioning valve/distribution block.
Yeah pumping it up gives it better feel. Nothing leaks, as far as me or the shop could tell. I'll try the fuse later today.
 

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Discussion Starter · #7 ·
Might be abs related... Pull the fuse for the abs and take it for a ride see if it changes. Probably not. Bad abs is usually not a squishy pedal.

If you drive and press the brake...let off real fast and hit it again is the pedal good then?(pumping the pedal)....if so its probably something like the power boster.
Listen for leaks or spray something around it to check.

If that's not it you'll be moving to a proportioning valve/distribution block.
Ok I tested with the abs fuses. For the first like 5 or so stops it seemed to help, but then it went back to super squishy. Not sure what it means
 

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I'm guessing it's not abs. Get you a spray bottle with soapy water. Have someone pump on the brake while you spray in-between the master cylinder and booster,also behind the brake booster on the firewall side. Watch for air bubbles. If you see bubbles your brake booster is leaking.

If it's not that it's going to be the proportion valve/distribution block or the rubber hoses. I'm not going to be much more help without being there.
 

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I disagree. A lacking brake booster will give you a hard pedal and never a soft pedal. Abs would likely give you a hard pedal or a jumpy pedal. You have air in the system.

If this all was ok before the work, you have air. Just have someone pump and hold the pedal while you bleed. Close and repeat.

Collapsed brake lines do happen. The way to check this is break the bleeder loose. It should drip at a good rate once or twice per second. If nothing, collapsed brake line. But is this is new after the brake work, you have air.
 
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Discussion Starter · #11 ·
I disagree. A lacking brake booster will give you a hard pedal and never a soft pedal. Abs would likely give you a hard pedal or a jumpy pedal. You have air in the system.

If this all was ok before the work, you have air. Just have someone pump and hold the pedal while you bleed. Close and repeat.

Collapsed brake lines do happen. The way to check this is break the bleeder loose. It should drip at a good rate once or twice per second. If nothing, collapsed brake line. But is this is new after the brake work, you have air.
Im reasonably confident there's no air in the system. both me and the shop bleed it multiple times, and they even vacuum flushed the system twice.
 

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Bad break booster definitely a hard pedal like a brick. I have found a few that bleed off air as your pressing the pedal. Giving a squishy feel on the first pump. Then a fast second pump catches the pressure up and gives a normal feel to the break. Used to find this more with old classics. Mines actually doing it now, I'll try to get a video of it tomorrow in the light. I agree the abs would feel like jacking off the brake pedal. There's a ton of things it could be and I Ain't trying to start sht I'm the new guy lol.
 

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Oh yeah you had a different symptom tho. That hardly ever happens. Thats the vacuum half so yeah I could see a slight loss in vacuum making the pedal harder.

Do you have a lean code?
 
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No code on mine. It leaks just enough to screw up how the pedal feels. Just for now... I give the brake a slight pump release then apply brake as needed.

That's easy to over look and you can't really hear the air unless it's wet. If you know to look it's easy to see. Only reason I mentioned it.

Hardly ever happens you got that right almost never.
 

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Honestly Brother you know your own car and you know what it has and has not been exposed to and no FWD car known to man is capable of a 180 degree turning radius so stretched or pulled brake lines are not on my list. Unless you squeezed your lines using locking pliers when you were changing your caliper the lines themself should dry and crack away before they cavitate but I have seen a lot of strange SCHIDT in my days so I put nothing past nobody...

But you got air in your system, reading your FIRST post I look back at my 2005 which I went through two reman master cylinders, measured seals and rebuilt OEM myself, a BNIB Brake Booster by Dorman, four bnib Goodrige lines, and two rear reman calipers WTF...

Trust me fellow B15U-er you have air in your system and it got in when you opened up a line, the more you press the brake pedal the more you cause the air pocket to move through your braking system until it hits that nirvana spot and cavitates there making your car inoperable...

I will post up here exactly what you need to buy and with some searching you can find YouTube videos on how it works. This hand-held pump will affix to your master cylinder and the brake fluid is pressurized up to 15psi and it will remove the air from your system by starting at the master cylinder working it down and out from the master down to the calipers.

Bleeding at the caliper I have experience with this method and air getting sucked in around the bleeder nipple threads and entering the system so pushing the fluid into the system from the master cylinder (like the dealer does it) is the way to go.

My last tip for you: Because your system is so GROSSLY full of air, like mine was LLS you cannot bleed it the way YouTube tells you too... You have a split system you will because of excess air ingestion open front left and rear right at same time, why? You have a split system and this will remove air from this entire quadrant on the master cylinder allow to set open for 2-3 minutes then close them both. Then refill the hand pump machine with fluid again and re-pressurize it again and THEN open your front right and rear left together allow to bleed for 2-3 minutes USE A WATCH then close them off.

Fire up your new skool SR20 and test drive it, call me (text first) let me chew your ear for 5 minutes I will make this schidt make sense, 1-240-429-8297 hell this car is the poster child for 2JR and V1R but I almost was about to junk this father phuker because of no brake pressure
 

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