Front Brakes Locking Up!

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Mar 5, 2023 | 11:07 AM

Zsnyder5

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Heel & Toe

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Front Brakes Locking Up!

I’ve found myself in a tricky situation here. Car is an 02 z06 that I have been trying to fix a low pedal on. Here recently after a few minutes of driving the car feels like it’s driving into a strong headwind. Im suspecting the front brakes are always engaged slightly as the pads are very low when they were wider than 8mm just a month ago... the rears dont seem to have worn nearly as bad. Today though the fronts actually locked up while driving! I replaced the master cylinder and bled the system thoroughly but to no avail the brakes are still sticking and low pedal. I plan on borrowing a scan tool later to try and bleed the ebcm as that could help get air out of the system. The most puzzling of all of this though is that if I throw the car in neutral while driving the brakes are fully released. Could this be a problem with the BPMV or is it most likely air in the system?

Mar 5, 2023 | 11:13 AM

Supercharged111

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From: Da U.P.

Is it one or both fronts locking up? I ask because a collapsed brake hose will cause a brake to hang up like that.

Mar 5, 2023 | 11:29 AM

C5 Diag

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From: Cape Coral, Florida

If you have a scan tool or by using the DIC see what codes you may have stored.

Mar 5, 2023 | 11:31 AM

Zsnyder5

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It was definitely both today. Also the car doesnt pull in either direction- braking or not

Mar 5, 2023 | 11:33 AM

Zsnyder5

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Quote:

Originally Posted by C5 Diag

If you have a scan tool or by using the DIC see what codes you may have stored.

There are no codes stored in the DIC although I’m hoping when I service bleed the module i can do a more in-depth code read as well.

Mar 5, 2023 | 01:16 PM

Johnny B Goos

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I would also check the slide pins on the calipers to make sure they are lubed and not broken or missing

worst case scenario, if you need to rebuild them it is very very simple just some compressed air to pop out the pistons

make sure your master is working properly as well

Mar 7, 2023 | 09:30 PM

Zsnyder5

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Update- re-bled the master, replaced both hoses and was able to borrow known good c5 front calipers from a friend and used a scan tool to bleed the ebcm. The pedal feel is way better but the car still dives when letting off the throttle. After a little driving the fronts are hot but the rears have little heat to them. No codes for abs/tcs either. I followed all the lines and hoses and found no obvious leaks or kinks. Still with the clutch in or in neutral the car feels normal

Mar 31, 2023 | 09:57 PM

Zsnyder5

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So I was actually fighting two different issues here... Got a new booster which fixed the low pedal and have not had any more issues with the brakes locking up but after the install the car still felt like it was lurching or dragging- no matter the gear but, again, it goes away in neutral. As I drove it more and more I noticed I felt it on decel or letting off the gas the most but could also feel the dragging/lurching on acceleration too. Turned my attention to the air/fuel delivery and found the underside of the air filter was absolutely FILLED with dust and could have probably passed for building insulation! Removed the intake and took it for a short drive and it ran better than it ever did! Got a new filter and all is well again.