Hello guys. I did a search of all dates related to brakes locking up, but didn't find anything pertinent.
Car: 1999 Pontiac Sunfire SE Coupe
Brake Mods: Brembo Sport drilled rotors, Performance Friction Carbon Metallic Pads
Here is the deal. This phenomenon is most noticeable when it is wet. I will press down on the brake and with just enough pressure to get the pads to start engaging the rotors the brakes all lock up tight. The car slides. After about a second of lockup, there is a loud pop, it releases for another second, then lock up again until I stop. After a second loud pop while I'm stopping I hear a vibrating sound, resembles a spring being bent over and released, that kind of metallic "boing" sound. I try drying the brakes off when I first start driving and it doesn't help much. I've taken it to a brake specialist and not only did they say it is in fine, but there is more than half the life left in the pads with no rotor problems.
Anyone else have this problem. My first thought was ABS. I know it helps grip and release so you don't slide. But my understanding was that ABS was supposed to grip and release pressure several times a second, faster than a person could modulate the pedal. This is much longer than that. My other thought was that I just ended up with a car without ABS. Perfectly likely. My problem with that idea is, however, that it locks and releases under constant pressure. Doesn't makes sense to me.
If anyone has similar experience and help me figure out what is going on, that would be great. Any ideas or suggestions on where to find more info would be great. Thanks in advance for any help everyone.
yup, thats our abs.
mine goes "POP dungggggggggggggg" which sounds like your pop and spring thing. thats just the way it works. its a pos system, what do you expect, its an econo car
final answer: you're fine
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- Sold my beloved J in April 2010 -
That's what I had thought. But my girlfriend freaks out everytime it happens. Now I can atleast say that I was right, normal.
just lay easy on the brakes when in the rain, and get new tires to stop the hydroplaning.
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- Sold my beloved J in April 2010 -
That's what I've been doing. Problem comes when I'm easing into the brakes as much as possible and then as soon as there is contact made they lock. But I'm getting used to it. The tires are a different thing. Toyo Proxes with what should be about 20,000 miles left on them and still has plenty of tread. They shouldn't be giving me problems, but I think they have worn fast. I'm looking at some Traction T/A H's next (440 AA A).
well, they shouldn't be locking up if you're going easy on it. perhaps its the roads you're driving on, or, you might just have a problem (too much pressure).
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- Sold my beloved J in April 2010 -
oh i just thought of something else. perhaps you have air in the lines. so whats happening is you're easing into it (compressing the air), and eventually you hit a point where the air doesn't compress anymore, and by that time, you're putting in a lot of pressure. perhaps bleed the system?
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- Sold my beloved J in April 2010 -
Hmmm, that's a good possibility. It's about time to replace all the fluid anyway.
You have Traction Control don't you (even if it's turned off). If so, you almost certainly have air in the ABS/TC module (or tons of water and/or other crud). Could need anything from a good bleeding, to taking it out of the car to do a good flushing and cleaning.
