1991 Civic DX Hatchback, all bone stock, front disc / rear drums, no ABS.

Most of the time the brakes have MASSIVE amounts of brake power...I am convinced I could lock all fours with one finger (or toe) on the pedal. But then sometimes they feel fairly normal; you never quite know what you are going to get when you hit the brakes.

I have recently replaced the master cylinder, successfully bled the brakes and replaced (flushed) all brake fluid while at it...the system is clean as far as I know. I also verified that the booster is holding pressure as it should and there are no odd wear patterns at the pads/rotors or shoes/drums.

Just this past weekend the car passed the NY state vehicle inspection with no hint of any problems so it is not something very obvious.

I have been doing my own work on many vehicles for 30+ years, but this one has me baffled. Any ideas anyone? The Russian-Roulette brakes game has been fascinating, but I have had enough of the fun now.

 

Check your rotors for lateral runout...if it's too great, the rotors could be pushing the pad/piston back into the calipers. Just a thought...
Or check the slide pins on the calipers. They could be sticking/freeing/sticking in a different spot, which might cause your inconsistency, as well.
In any case, I'm fairly certain you'll find the problem in the disc setup, rather than the drums.


Modified by WERA689 at 1:58 AM 11/4/2008

 

Sounds like a booster problem *shrug*

 

Not really, a bad booster would cause a hard (unassisted) pedal. I would agree with WERA, thoroughly check over your calipers and clean up and lubricate the slide pins. Check for pads and shoes saturated in fluid. That can cause brake grab.