My brakes have been locking up on me for no reason. It's been happening for about 2 weeks now. At first I didn't think anything of it, but i began to realize my pedal was becomming very sensitive. If i pressed it with any force at all, it would lock up the front brakes automatically the first one or two times i'd stop after i started the car. Then they began to lock up on their own when i was making k-turns. It would happen when i cut the wheel all the way to the left to the lock with my foot on the gas and the clutch pedals; nowhere near the brakes. Then the other night i was going to pull out of a parking spot, and practically did a brakestand while trying to pull out, once again feet on the other pedals, nowhere near the brake. I replaced both front calipers today and checked the rotors for signs of warping. The rotors looked fine, so we put them back on and bled the front brakes. it worked fine for like an hour, but i let the car sit by my friend's house while we went to the movies, and when i went to leave and make a k-turn, they locked up on their own again. Can someone please help me with this problem, i'm getting worried they're going to lock up on the highway or something next. Any suggestions as to what it could be are GREATLY appreciated, or if this has happened to you, PLEASE let me know what it was. Thanks in advance.

 

They lock-up all by themselves w/o your foot even touching the brake pedal?

 

Yeah, all by themselves. Usually they're either locked already when i first go to move the car, or they lock up when i'm making the k-turn to leave my street. I don't understand it.

 

i had the same problem with my front right brake about 4 years ago before i put it in storage and it had turned out to be the rubber brake line going to the caliper. just got it out of storage two weeks ago and left side was doing it replaced left line and it went away.

 

what exactly was wrong with the line, was it kinking, leaking, etc? because i'm really not looking foward to taking it off and having to bleed the whole brake system, but i'll take a look at it, thanks a lot.

 

half way between where the line connects from the hard line to the caliper there is a bracket which helps hold the line away from the tire. it does this by twisting the line and over time the line just becomes weak like all rubber. you could see it there when i took off the lines, this was my scenerio when i lived in virginia my brakes worked fine, moved to florida worked fine except when stuck in traffic on smoldering hot days would apply brakes and they would stop fine let go of brakes and in the begining the right brake would not release. it was pushing fluid to close the caliper but when it would try to suck the fluid from the caliper to release the brakes the line would internally collapse like with a straw and would block the fluid. this is just what happend to me not only once but twice, and both times changing the line fixed it the lines were only like twenty some dollers at any part store. which ever line you replace is the only wheel you need to bleed. that is all i did that is what we do on aircraft too.