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Discussion Starter · #1 ·
This is the 2nd time my brakes locked!

The first time was when I was going to the San Jose meet on the 22nd. I was cruising down the hwy, then all of a sudden my car felt really sluggish. I'm supposed to be going alot faster at 3k in 5th...so I down shifted to 4, and still no difference. So I pulled over on the street I exit to get to the complex where everyone is at, but I wasn't there. I get out the car, my car over heats and starts spewing out shit from the overflow tank, my brakes are SMOKING and yeah. I called David (driftedmk3) and he asks a few people and they tell me to pull my abs relay. So I do. and my brakes work again.

Now today, I was coming home from work. I hit a stop light, my car feels hella sluggish. I think to my self...not again. so I pull into the church parking lot near me and it was locked. No smoke though. No over heating. I pull the relay, still doesn't work. My Master cylinder works(depressed the pedal, stays there) It has fluid in it. My brake lines are good, no leaking. My calipers are fairly new, about a year and a half old. Help the poopra :(
 

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this maybe a shot in the dark but whens the last time you did a complete brake fluid flush... I know when water gets in it it causes the fluid to boil and fuck with the brakes... but I dunno if it would cause it to do that much.
 

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Is it both front and rear that are locking, and is it specific to one side or both sides?
If it's just the front, Open the calipers, inspect the pistons and reseat the brake pads.
 

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Discussion Starter · #4 ·
It's both front and rear. I barely made it home. I was hitting 9psi and it was barely moving.
 

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Bully
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Wow, Sucks that it happened again. Hope you get it fixed.
Btw did you get the down pipe in?
 

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Addicted to oil
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I had these same symptoms on an Acura I used to own. The brakes would lock up every hour or so then be completely fine a minute later. The problem was a bad brake booster.

Dennis
 

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As sacto said, flush the fluid completely, as contaminants can cause a lockup, in your case, possibly the master, as all wheels are affected.
 

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Had a similar issue once when I replaced the master cylinder... all the wheels seemed to be dragging. Replaced the master and all was good...

So, if you've not replaced the master in the last few years, I'd go ahead and do it and flush the system while you're at it. I dunno what the "real" symptoms of a bad booster are, other than being hard to stop. Good luck!
 

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Always playing catch up
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um, if the master cyc. went, wouldn't it be like not having any pressure at the petal (like someone cut a line)? thats what happened when my master went out. i am also saying the brake booster

<l><l>
 

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Well... The original master cylinder had that kind of issue (lost pressure)... I replaced it and the remanufactured unit somehow malfunctioned and was putting pressure on all the wheels, even when the brake pedal was not applied. Then, I replaced that one (it had lifetime warranty) and all was good again.

Only a few ways to tell what's really going on and like anything else, start with the easiest, lowest cost item first. There may be ways to troubleshoot the brake booster in the TRSM (without having to remove it 1st).

That's why I suggested that if it had been awhile, might as well replace the master cylinder and go from there. Costs about $50 w/warranty from almost anywhere and takes about 10-20 minutes to swap....
 

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SecretService.jp
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My master cylinder is giving out as when you're stopped at a light applying even pressure on the brake pedal, it'll slowly release the brakes. A quick pump and it's fine, but when you're knackered coming from work, you've got other things on your mind, hehe. Not to mention tapping the guy in front (or behind) of you.

~Cheers~
 

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Discussion Starter · #14 ·
My brake booster is good! I pulled the vacuum line on it and the booster still sucks in like like it should. BTW, let me clarify when I depress the pedal. What happens is when I press down on the pedal, it goes down to some point...and it stays there. once I take my foot off, it comes back come. Sorry for the misconception. Now it's wierd, because last night I started it, to get it up my drive way so I can jack it up, but my brakes worked again. All the times this happened to my car, have been when it was hot. Does that have anything to do with it?

BTW I know how it feels to have my brakes shot. Happened to my beater, '93 Accord. The brake pedal went down so quick, and wouldn't come back up. I had to brake with my e brake -_-.
 
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ive had problems with my caliper mounts being bent for some odd reason. had to replace both fronts with "loaded" calipers because when i put on fresh pads they would bind on the rotor, but not til i tightened the lug nuts.
 

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Discussion Starter · #16 ·
Damn it they locked again today when I went to go to the shop to have my shit checked out.

The dood said it was either my preportioning(sp?) Valve or...I forgot which one he said it was... my calipers or brake pads.
 

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change the brake distribution block (located at left side shock tower)this little unit has a check valve in it and it is probably clogged.......had the same problem with a friends supra recently and about went crazy trying to figure it out
 
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The verry exact thing(vapor locking) happined to my MKII it will get worse verry fast over a couple weeks the reason was the valve in the middle of the brakline & the caliper seals were brittle and cracked. Valve used was thrown in tool box while browsing pick a crap and the seals were like 12$ from autozone.
 

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just like to add useing transmission fluid in you brakes will cause the seal and everything to swell. causeing them to lock up when heated. i know you used dot3 break fluid. but just wanted to add something here.
 

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Discussion Starter · #20 ·
Can someone go into more detail about this distribution block and vapor locking?
 
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