Front Brakes Will Not Release

[Jposey66]

Front brakes will not release.

This started out with me thinking the right front caliper was seized. Nursed it home and just went ahead and ordered all the stuff for Cobra brake upgrade. Once parts arrive, I put it up in the air and realized that it wasn't just the right front. It is both fronts. The pistons will not push back in. Cracked both the banjo bolt and the upstream end of the rubber hose and the piston will push right in, no problem. Anyone had this issue before? ABS? Proportioning valve? Master cylinder?
Wanna get this sorted out now, before doing the Cobra swap.
It's a 97 GT
Thanks guys!

 

[lwarrior1016]

Did you get fluid out of the fitting at the top of the rubber hose? Meaning the hoses aren’t collapsed and they let fluid pass.

It could be a failed abs block.

 

[Jposey66]

Correct,when I loosened the upstream end of the rubber hose, I was able to push fluid out there by pushing that caliper piston in. Tells me it has to be something upstream from there. Curious if there's a common failure upstream.

Thanks,
Jeff

 

[Jposey66]

Update: Piddled with it a bit last night. There seems to be some issue between the hydroboost and the master cylinder. I loosened the two bolts, holding the two together, just a few turn and the brakes no longer lock up. I'm able to apply the brakes and they release normally. As soon as I tighten those two bolts back up, I'm back to the original problem. Apply brakes and they do not release. It's almost as if the push rod is too long, but these parts have been in there for months and have been working fine. I crawled under the dash and disconnect that push rod from the brake pedal and that didn't help.

 

[Kasdan]

its the master. had it happen on a couple different cars.