Many brake combos, same problems.
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This is a discussion on Many brake combos, same problems. within the General Maintenance, Troubleshooting & Accidents. forums, part of the Tech & Modifying & General Repairs category; Hey all, I'm bringing this up once again in the hopes that one of you will be able to help ...

  1. #1
    Registered User Tinywagon's Avatar
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    Many brake combos, same problems.

    Hey all,

    I'm bringing this up once again in the hopes that one of you will be able to help me. I have a 2002 wrx wagon with a 4eat and ~115K miles. I purchased the car used and it has constantly had the problem of not being able to stop properly when the car is cold, and an almost constantly spongy pedal.

    this means that when the car is in D, and I stop for the first time after starting the car, i need to shift it into neutral in order for the brakes to stop my car. If I leave the car in D then I need to leave quite a bit more distance in front of me if I wish to stop in time. This is because the pedal goes to the floor and the brakes will not be able to stop the car from "powering through" them, I'm not to sure how else to describe it. However when I shift it into neutral the car stops and rests just fine, and the RPMs jump up in order to warm up the car. After a few minutes when the car warms up it stops just fine.

    This has happened the exact same way in all four seasons, with the following setups, over the past few years.

    Setup one: Bone stock. stock pads, stock rotors, fluid etc...

    Setup two: Drilled Brembo Rotors front and rear, metal matrix track pads, SS brake lines and Super Blue Fluid.

    Setup Three (Current): Stock rotors, Hawk HPS pads, SS brake lines, Super Blue fluid.

    When switching to the current setup, I had a professional subaru mechanic do the brakes for me. He installed the rotors and pads and did a full brake bleed. When he was done, he found that the old drilled rear rotors were so warped that they couldn't even be turned.

    I never felt any kind of vibration when I was driving on that setup. Not sure what that means.

    At any rate, Im at a loss. Two days ago I had to make a panic stop and I felt the pedal bounce off the floor. Since then I have not been driving my wagon and I have been considering the various scenarios.

    I am not leaking fluid anywhere.

    The brakes have been bled and no kind of air is found.

    The calipers show no sign of drag.

    The pads are about a month old and have around 1500 miles on them, they also show even signs of wear.


    Short of installing a new MC/BB or somehow finding a 5/6MT to swap in, I am at a loss.

    Any advice would be great.

    Thanks in advance.

    -Tiny
    Last edited by Tinywagon; 02-13-2012 at 11:40 PM.
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  3. #2
    Moderator Donkey's Avatar
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    This has nothing to do with your transmission. I would be looking at the MC. Do the brakes get better if pumped?
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    Registered User The Gator's Avatar
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    You said spongy pedal. If you arent getting any back pressure that would seem to be an indication of the master cylinder having a seal problem.
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  5. #4
    Registered User Tinywagon's Avatar
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    Quote Originally Posted by Donkey View Post
    This has nothing to do with your transmission. I would be looking at the MC. Do the brakes get better if pumped?
    Yes after two or three pumps the pedal gets more firm.
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    The Fruit mangostick's Avatar
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    ^ change out the master cyl. I'll put lunch on that being the problem. Likely has been all along esp given the mileage on the car.
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  7. #6
    Moderator Donkey's Avatar
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    The brake booster on the 02-5 WRX's are a little weird. They are supposed to be a "dual/tandom stage" to allow for better pedal feel and brake control.

    "Subaru, along with most other car manufactures, uses a dual stage vacuum booster on the brake master cylinder. It is intended to satisfy the majority of men and women who do not want a car that requires heavy effort to control. For this reason the Subaru steering is kept light and the transmission shifts with ease.
    Here is how it works: The brake pedal is depressed perhaps an inch and the car stops medium hard. Simple physics tells you that if you press twice as hard on the pedal the car line pressure will go up by only the square root of that increase in foot pressure.. This means that as you get into the brake pedal it should get rapidly harder and harder as the car stops more quickly. But the Subaru pedal stays soft. What is going on?
    The dual stage vacuum booster has one level of assist in the first part of its stroke and as the brake pedal is pushed in, a port is opened on a second, much more powerful boost stage then compensates for the large increase in actual brake line pressure. The pedal stays relatively soft even as the ABS kicks in.
    When driving the car hard, a double clutch down shift is done with the ball of your foot working as the pivot on the brake pedal as you heel, or the side of your foot presses and releases the gas pedal. Many drivers are finding that this soft brake pedal inhibits there ability to modulate both the brake and the throttle smoothly. How do we fix this problem?
    SPD Tuning Service offers a single stage booster for the Subaru that replaces the larger dual stage booster. The pedal becomes remarkably firmer and easier to read, while still keeping the relatively light control inputs that are a Subaru characteristic. This is especially true when pushing deeply into the brakes during high performance driving. You gain a firm place, the brake pedal, from which your foot can rev the engine for smooth take-up of the drive train during critical braking maneuvers and even more important your foot can roll off the brake pedal and into the gas during the turn in down to the apex of the corner. The ability to get a smooth transition of weight off the nose of the car during turn-in is the hallmark of a smooth, quick driver. To achieve this one needs a proper seat and pedal combination. The pre-1999 cars use the booster kit alone. Unfortunately, the 1999 and later cars have a redesigned master cylinder/booster that is not interchangeable. We can still provide the single stage booster kit, but 1999 and later cars will require a new master cylinder at an additional expense."

    Last edited by Donkey; 02-14-2012 at 10:29 AM.
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  8. #7
    The Fruit mangostick's Avatar
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    that IS odd.. hmm... but a worn or malfunctioning booster should leave a hard pedal and diminished braking...... at least a traditional setup would anyway.
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  9. #8
    Administrator Trainrex's Avatar
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    Quote Originally Posted by Tinywagon View Post
    Hey all,

    I'm bringing this up once again in the hopes that one of you will be able to help me. I have a 2002 wrx wagon with a 4eat and ~115K miles. I purchased the car used and it has constantly had the problem of not being able to stop properly when the car is cold, and an almost constantly spongy pedal.

    this means that when the car is in D, and I stop for the first time after starting the car, i need to shift it into neutral in order for the brakes to stop my car. If I leave the car in D then I need to leave quite a bit more distance in front of me if I wish to stop in time. This is because the pedal goes to the floor and the brakes will not be able to stop the car from "powering through" them, I'm not to sure how else to describe it. However when I shift it into neutral the car stops and rests just fine, and the RPMs jump up in order to warm up the car. After a few minutes when the car warms up it stops just fine.

    This has happened the exact same way in all four seasons, with the following setups, over the past few years.

    Setup one: Bone stock. stock pads, stock rotors, fluid etc...

    Setup two: Drilled Brembo Rotors front and rear, metal matrix track pads, SS brake lines and Super Blue Fluid.

    Setup Three (Current): Stock rotors, Hawk HPS pads, SS brake lines, Super Blue fluid.

    When switching to the current setup, I had a professional subaru mechanic do the brakes for me. He installed the rotors and pads and did a full brake bleed. When he was done, he found that the old drilled rear rotors were so warped that they couldn't even be turned.

    I never felt any kind of vibration when I was driving on that setup. Not sure what that means.

    At any rate, Im at a loss. Two days ago I had to make a panic stop and I felt the pedal bounce off the floor. Since then I have not been driving my wagon and I have been considering the various scenarios.

    I am not leaking fluid anywhere.

    The brakes have been bled and no kind of air is found.

    The calipers show no sign of drag.

    The pads are about a month old and have around 1500 miles on them, they also show even signs of wear.


    Short of installing a new MC/BB or somehow finding a 5/6MT to swap in, I am at a loss.

    Any advice would be great.

    Thanks in advance.

    -Tiny
    Which pads did you have installed after you last posted?

    Quote Originally Posted by Tinywagon View Post
    1/7/12
    I had all four rotors replaced as well as new pads put on and the entire system was bled with new fluid two weeks ago and my mechanic, a subaru specialist, told me that my rear rotors were extremely warped, so much so that they could not be machined, a phenomenon he had never seen. Especially considering that the rotors were only two years old.
    Have you followed any advice that we gave you or are you hoping it fixes itself?

    Quote Originally Posted by Trainrex View Post
    1/9/12

    You have air in your lines and/or your master cylinder is faulty. Naturally this is assuming you don't have a fluid leak somewhere. Odds are the master is just fine. You need to properly bleed your brakes before you drive any further. Whomever installed the Goodrige lines did not properly bleed the system.

  10. #9
    Pro Manscaper Mikie13's Avatar
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    And if you swap out the MC, get an MC Brace as well...
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  11. #10
    Registered User Tinywagon's Avatar
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    Quote Originally Posted by Trainrex View Post
    Which pads did you have installed after you last posted?



    Have you followed any advice that we gave you or are you hoping it fixes itself?
    I still have the Same Hawk HPS pads. I also bled the lines two more times since I last posted, I use the "caliper tap" method, with a rubber mallet and found no additional air. And I checked all the hard/soft lines I could for leaks and found none. I took your advice, so don't sound so irritated. But I just wanted to make sure I was buying the right part, before I threw more money at a problem that doesn't seem to go away.
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  12. #11
    Administrator Trainrex's Avatar
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    Quote Originally Posted by Tinywagon View Post
    I still have the Same Hawk HPS pads. I also bled the lines two more times since I last posted, I use the "caliper tap" method, with a rubber mallet. And I checked all the hard/soft lines I could for leaks and found none. I took your advice, so don't sound so hurt. But I just wanted to make sure I was buying the right part, before I threw more money at a problem that doesn't seem to go away.
    What the *** is the caliper tap method, and who the *** taught you that?



    Edit: If you are without help, buy yourself a set of speed bleeders.

  13. #12
    Registered User Tinywagon's Avatar
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    Quote Originally Posted by Trainrex View Post
    What the *** is the caliper tap method, and who the *** taught you that?
    Lol, yeah it sounds weird, but it's just taking a soft rubber mallet and lightly tapping the calipers while the bleed screw is open and under pressure. It's worked in the past, serves to move trapped air. My boss taught it to me, he used to race Porsches.
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  14. #13
    Administrator Trainrex's Avatar
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    Quote Originally Posted by Tinywagon View Post
    Lol, yeah it sounds weird, but it's just taking a soft rubber mallet and lightly tapping the calipers while the bleed screw is open and under pressure. It's worked in the past, serves to move trapped air. My boss taught it to me, he used to race Porsches.
    Try doing it correctly.

  15. #14
    Moderator Donkey's Avatar
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    I added some more info about the brake booster in my last post. I do agree with Trainrex,speedbleeders and/or a mightyvac do wonders for a brake bleeding job. Also make sure you do the correct bleeding sequence.
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  16. #15
    Registered User Tinywagon's Avatar
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    Quote Originally Posted by Trainrex View Post
    Try doing it correctly.
    Dude, really? What's your problem? RF, LR, LF, RR every time. The tap was just something else I tried, and it has gotten air out in the past.

    Quote Originally Posted by Donkey View Post
    I added some more info about the brake booster in my last post. I do agree with Trainrex,speedbleeders and/or a mightyvac do wonders for a brake bleeding job. Also make sure you do the correct bleeding sequence.
    Thanks for the information, I didn't know that about the dual stage booster. I have some speedbleeders, but I also have a friend that helps me do the bleeding. I'm not looking for a decrease in stopping distance over stock or anything, i'm just looking to get my brakes back to stock condition, will a single stage booster have any effect on this or is it just a "pedal feel" mod?
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