new brakes suck...

[mikeinaus]

i bought my mx3 back in may and the entire time i drove it the one of the rear calipers was seazed in place and the other only really worked with the e-brake on and half assed at that. however my braking for the most part was really responsive for just my front brakes. i replaced my rear calipers/rotors/pads and my brakes feel alot worse now. i didnt notice it so much at first but there pretty bad now. i just re-bled my lines the other day and that didnt really help much.

the problem is:
i can push the brake pedal down about 2" before any kind of force is applied. at about 3/4 of the way down i can slow down at an alright pace. if i slam on the brakes as hard as i can i can make them lock up but for average braking they just dont feel right. its pretty hard to explain what im experiencing. there ok for light or hard braking but the middle point just doesnt seem to be there. they also feel pretty sluggish like they react slowly... ive already rear ended someone because of this and ive had to alter my driving style to giving alot of room to people infront of my and relying mainly on down shifting to slow down. anyone have any idea what could be wrong or what i should look at?

[umcamara]

I'm not sure what you're braking problem is, but there's nothing wrong with having one less tail-gater on the road. Tail-gaters annoy the hell outta me.

Your proportioning valve may not be allowing the required pressure to the back wheels. I'm not sure how common it is for a PV to fail, but I have seen it.

[mikeinaus]

wasnt "tail-gating" when i hit the car. i was changing into a different lane and the person infront of me slammed on her brakes from highway speeds to a complete stop. i was almost stopped when i hit her car but it was still fast enough to damage my hood and bump, but leave her car with a small scratch.

i forgot to say my e-brake is also pretty easy to pull up. most e-brakes ive used require alot of force to get them to the top position but i can do mine fairly easily.

[umcamara]

wasnt "tail-gating" when i hit the car. i was changing into a different lane and the person infront of me slammed on her brakes from highway speeds to a complete stop. i was almost stopped when i hit her car but it was still fast enough to damage my hood and bump, but leave her car with a small scratch.

i forgot to say my e-brake is also pretty easy to pull up. most e-brakes ive used require alot of force to get them to the top position but i can do mine fairly easily.

I said tail-gating because you said you had to adjust your driving style to leaving room before you and the person in front of you. Pretty good idea if you ask me.

And don't acknowledge my advice on proportioning valve. Good call!

[mikeinaus]

sorry i didnt mean to discount your advice. ill have a look into it and i hope your right . i dont know much about brakes so ill probably just get a shop to look at them for me. i was just looking for advice to help pinpoint the problem. is it normal to have to push the pedal down 2" before it starts to brake?

when i said leave room i meant leave alot of room... like way more then usual, i almost never use my brakes anymore 70% of my braking is my downshift.

[_-Night-Shade-_]

First of all let's address the most basic and important things. Is your brake fluid full? How does the pedal feel? If it's spongy and very easy to press down you probably have excessive air in the system and needs to bled, which would explain why your brakes are ineffective.

[mikeinaus]

fluid was low and i thought it was just air in the lines but solo_ryder came over a few days ago and helped me bleed them. he said there wasnt much air in the lines but one of them was pretty dirty. fluid is topped up now and there still pretty bad. better then before but still not good. i dont have abs so when i slam them they should lockup right?

is there a way to adjust the pedal or something? feels like a bicycle when the cable isnt adjusted properly so they dont pinch hard enough. but i have hydrolic lines so that shouldnt really matter. is there a pump or something thats not pumping enough pressure in the lines? should i replace my lines? first time i flushed them i filled the fluid to full and within 2 months it was down to the low line. perhaps i have a leak somewhere?

[_-Night-Shade-_]

You probably have a leak. A loose handbrake shouldn't affect braking while driving. If your brake booster wasn't working it would be really hard to push the pedal (try doing it with the car off to see what I mean). If all else fails then maybe you do have a bad proportioning valve or the calipers themselves.

[mikeinaus]

where is the proportioning valve located? is there a way i can test it or do i just have to replace it and see if that works?

[_-Night-Shade-_]

where is the proportioning valve located? is there a way i can test it or do i just have to replace it and see if that works?

Don't know much about that, I'm guessing around the master cylinder. Same thing for testing/replacing it - someone with more knowledge on here should be able to tell you.

[_-Night-Shade-_]

Forgot to add: if you pump the brake pedal with the car OFF you should only be able to fully depress it about 3 or 4 times, if you can still get movement out of it that tells you either air is still in the system or you have a leak somewhere. Either way the system isn't under full pressure and you won't be able to make full use of your brakes.

[umcamara]

The proportioning valve is on the firewall in the middle, but a little closer to the passenger side I believe. You can't miss it, there's four brake lines connected to it.

I believe you can adjust brake pedal play, I know for sure you can adjust clutch pedal play. It's done at the pedal by playing with a nut (that's what she said).

[Mad Cow]

You might have a hairline crack in one of your brake lines. Check your fluid level, then pump the brakes about 10 times and check the level again. I had the same problem, turns out my power steering pulley rubbed through the front passenger side hard line and misted the engine bay with brake fluid every time you braked.

[PATDIESEL]

1. DO NOT EVER MESS with the porportioning valve. They are not supposed to be servicable. You can change the bias, but it is dangerous to do so. There is no reason to mess with it since it is set properly at the factory and does not ever change from use. Change it for a new one if anything. I do not think this is your problem though.
2. I would check a couple of things first. Make sure your front brake pads still have some decent pad on them. As they wear your pedal goes down more before the brakes actually start working. There is less thickness of the pad and rotor after some wear, so that the pedal is making up for that before making good contact. Make sense? So it might just be that your front brakes need some work since they were doing all of the work for however long. I cannot remember the required thickness of the rotor, but it has a minimum, you might need to replace them or the pad to get a solid feel back in the pedal. Check both front and rear pads sicne they can wear unevenly. You should also make sure that the slides on the front calipers are working well. The sliders make sure that the pads wear more evenly.
3. When bleeding the brake sysyem there is a pattern that you should bleed them in. This is a little known fact, but should be done this way every time. You always bleed from the furthest from the master cylinder wheel to the closest to the master cylinder wheel. So back passanger, back driver, front passanger, front driver. Now, some may argue that there are loops in the brake lines ot make them equal length. This is true, but the pattern should be followed as a general rule just in case you come apon a car that does not even out the lines (FYI, all cars should have even brake lines or the car would pull to one side for a moment right when the brake is applied). However, this rule makes 100% sure you get all of the air out of the lines when you bleed. You also need to bleed enough to make sure that All of the old fuild has left the line. For the rear brakes this can take some time. I usually just open the line and pump for a good 20-30 times. Then start the valve and pedal swap process to make sure you do not have any air at the valve.
4. Check for any fluid leaks near any brake line fitting. Start at the master cylinder and trace each one checking each fitting for any kind of fluid. If you see some fluid then you have found your issue.
5. If you have good brake pads all around, the rotors are in good shape and of better than minimum thickness, the calipers are sliding like they should, and the fluid is clean, new and without air and you still have issues then you need a new master cylinder and maybe a booster.
PS- make sure you are using a proper Line Wrench for the brake lines. A standard open ended wrench is dangerous to use on brake lines. One stripped fitting and you just cost yourself a ton of time. So take an hour or so and go buy the proper line wrenches before attempting to open or close any brake line fitting. The line wrench looks just like an open ended wrench, but the open end has the tips of the open end closer together. (if that makes any sense at all...)

[mikeinaus]

so i just took a couple of min to play with them. i think my problem is with the pedal. i can push the pedal down about 2" before my brake lights come on. is there away to adjust that?

nvm i found a guide. http://www.scoobymods.com/adjust_brake_ ... 271dfb4f38&" onclick="window.open(this.href);return false; i hope this works.