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98 SE - Brakes a little frightening

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Old 05-11-2007, 03:54 AM
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Default 98 SE - Brakes a little frightening

Brakes are acting very strange. For example, I had the car off and was able to press the brake pedal all the way to the floor with none of the normal effort required when the brake booster isn't active until about the 5th try, when it acted completely normal and became hard as a rock. I then started it, rolled forward and then applied the brakes as hard as possible, they didn't seem all that bad right then, so I did it a few more times and everything seemed ok. So by this time I had to get somewhere, so I hopped on the freeway and did some intermittent slowdowns and everything seemed perfectly normal. Then I come to the short SHORT freeway/median crossover/turnoff from 75 mph. Pedal IMMEDIATELY drops RIGHT to the floor and car slows like I'm only intending to slow down, running out of room fast, VERY fast, end up pumping the brakes about 3 times before anything really reacted. Then the rest of the braking and such was COMPLETELY normal. :? I just don't get it. I visually inspected the lines and master cylinder. The MC reservoir is still as full as it was BEFORE this started happening. Not leaking a drop. Now my thinking would be that if it were something to do with the ABS, the car would TELL me something! Like an ABS light? No lights on. Visually, MC looks brand spanking new. I know the brake booster is ok, because I know what it would feel like otherwise. The ONLY things I can narrow it down to are a bad MC or something to do with the ABS system.

Kinda dangerous. Help. Thanks.
Old 05-11-2007, 06:53 AM
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What you described is a typical failure of a master cylinder. The seals begin going bad inside.
Old 05-11-2007, 08:48 AM
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If you rename this topic "Bad Master Cylinder," you will have provided future searchers with a classic description of the problem.
Old 05-11-2007, 11:36 AM
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Do you have the Teves ABS system? If so its possible a bad wheel sensor is activating the abs and the pedal is going down.
Otherwise it sounds like bad seals in the master.
Try pulling the ABS computer fuse and test it in the driveway. If it doesn't do it with the abs disabled then a bad sensor is activating it.
Old 05-11-2007, 02:04 PM
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Well since its so intermittent, its hard to get any ironclad test results from it. And I didn't know 98s had the Teves :?: I thought that was only for 88-90 ABS :?: Anyways, Ok. Master Cylinder seals going bad. So is it a better idea to just rebuild it myself or just get a reman one? And also, just out of curiosity, is this normal for one to fail at only 88k? Sounds like some shoddy workmanship to me!
Old 05-11-2007, 02:53 PM
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Yep, just buy a reman - bench bleed it like the instructions tell you. And if you really want to finish the job properly, bleed all the brakes after you have tightened all the lines to the MC. Many don't do this, but there is no way you can open those lines without introducing air. Besides, that way you can do a manual flush of the old brake fluid. Just keep bleeding 'til the new fluid starts coming. If you haven't bled brakes before, make sure to keep the MC full so you don't introduce MORE air into the lines.
Old 05-11-2007, 03:01 PM
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WOW, I didn't know that they failed at such a low mileage. And then mine on the LE at 150k still feels perfect. Thats some crappy engineering. Why couldn't they just make these ones like they make the 87-91 gen? Idiots.

Anyways, thanks VERY much guys, don't know what I would do without yah. Just glad these things fail intermittently and not all at once, because I almost hit a very large cement bridge wall yesterday because of this.

thanks again
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