Stiff pedal with almost no brakes
04-04-2011, 07:57 PM
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Stiff pedal with almost no brakes My car sat for a few month after I blew my tranny and rear at the same time and I just fixed it. After i got it back together i lost my brakes. The pedal is very firm and barely slows the car down and it only goes about 1/4 of the way to the floor. I took out the broken 10 bolt and put in a 9 inch. After I swapped rears I moved the car and the brakes were fine. After that I swapped the 4l60e for a t56 and after I was done I went for a test drive to find the problem with the brakes. When I press on the brake pedal the whole master cyliner assembly moves a good inch or so and when I was bleeding the brakes the pedal would only go 1/4 way down until the bleeder was open then it would go all the way to the floor. I popped off the vaccuum line right on the booster and there is a little vaccuum but not alot. Does anyone have any idea what happened to my brakes?
04-12-2011, 08:48 AM
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I'd check for stuck pistons in the rear calipers. If the pedal moves freely when you open the bleeder, then there's no restriction in the lines getting to the caliper. If you jam those calipers around too much you can **** the piston crooked in the bore and it jams up.
04-12-2011, 10:07 AM
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Ok well I tried a few more things on my car. I took the boost gauge out of my WRX and hooked it up to the Vacuum lines in the Z28. It was only reading 12, from there i hooked it up before booster and eliminated the booster from the equation and it was still 12. From there I went to the line with the check valve by the throttle body and eliminated everything after it and it was at 12. I hooked everything back up and blocked off my MAF and put some air into the system and couldn't hear any air leaking other then at the MAF. Also I have a 228 228 588 112 cam installed but had no issues with brakes when it was in my automatic. Car is not tuned for the cam yet as it broke shortly after installation. Is 12 a high enough vacuum?
04-12-2011, 07:19 PM
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From what you're describing it sounds like your booster is shot, also 12 of vacuum should still give plenty of assist. Unless there is no vacuum getting to the booster I'd say it's a booster in your case.
04-14-2011, 11:16 AM
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The booster is what I was leaning towards, just wanted to have someone second it before I went out and bought one. Ordered it yesterday, i'll let you know if it solves my problem. Thanks to everyone for the input.
