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brake pedal not fully returning back...help

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Old 05-30-2006, 11:38 AM
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potsiewebber
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Default brake pedal not fully returning back...help

so, i purged all the brake caliper nips. 2x already and the master cyl. at first and last. the pedal is nice and firm when you push on it but it is not fully bouncing back to its original position. anyone know why this might be happening? i did notice that the 2 seals that seats the plastic reservoir is in are seeping just slightly.
Old 05-30-2006, 04:20 PM
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bump!
Old 05-30-2006, 05:54 PM
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AJK
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I had this same problem last year. Fortunately for me, a bleed of the slave cylinder solved the problem. I also adjusted the clutch pedal to the proper position including the over center helper spring. It's all a little hazy now, after a year, but if you have the manual follow it carefully and it may solve you r problem. Quite frankly, this was one of those times when you take it apart, find nothing wrong, put it back together and it works. Been OK since.
Old 05-30-2006, 10:37 PM
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oh yeah, this is an auto 93 gts
Old 05-31-2006, 12:06 AM
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Mrmerlin
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Hi what kind of fluid are you using in the brake system?
Old 05-31-2006, 10:27 AM
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dot 4 valvoline
Old 06-01-2006, 11:52 AM
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bump
Old 06-01-2006, 12:26 PM
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Mrmerlin
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Hi is that the synthetic stuff, if so i would get some ATE super blue racing and try rebleeding the system the syn fluid may make the rubbers soft in your brake system
Old 06-01-2006, 12:47 PM
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FlyingDog
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The brake fluid you're using is perfectly fine. I'd suspect the spring in the booster.
Old 06-04-2006, 11:19 AM
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thanks your thoughts. i do have another brake booster. i guess i will try and swap them.
Old 06-11-2006, 03:41 PM
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bump!
Old 06-11-2006, 03:42 PM
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I have replaced the master cyliner and changed brake fluids and the pedal is still too soft and not returning fully. help!!
Old 06-11-2006, 03:44 PM
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The springs in the master and booster should return the pedal whether or not the brakes are bled properly. Check them and check to see if the pedal is binding somehow.
Old 06-11-2006, 04:17 PM
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i just drove the car around the block. the pedal all the way to the floor stops the car and the abs comes on too. the pedaL is still not popping back up. i had the entire brake system apart. could there still be alot of air in the system?
Old 06-11-2006, 07:54 PM
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Herman K
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Default Same problem, solved mine, see picture

I just went through the same problem. I found that the brake fluid dirt/varnish built up in the in the master cylinder reservoir not only had attached it self to the site walls and bottom but also had clogged the fine mesh screen that are in the drains of the reservoir going in to the brake cylinder and thereby starving the brake fluid supply. I used BB’s and brake cleaning fluid to shake around until all the junk was gone and I had a clean reservoir. I have everything re-installed and it work fine. I have a manual 5 speed so the reservoir has a 3rd outlet for the clutch and the reservoir has a build in baffle for the clutch side supply. I got a few BB’s stuck in there and had to drill some small holes to push them out. The attached pictures should tell the whole story. If you have more questions than let me know.

94 GTS 5 spd


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