Lot of threads about rear caliper pistons not retracting, this not that! Actually had brakes and park brake all working top notch and went to the track. (Waterford hills). Worked great first session, second session, pedal started dropping a ways. Fortunately noticed it before getting on the track.
Finally noticed the left rear caliper piston retracting way too far after pumping brakes. Actually, watched the piston retract for five seconds. Ended up retracted a good 3/16, and bad enough the red brake light started flickering.

Anybody see this before?

I am about to take the caliper apart. Kinda hope to see a seal cooked or something like that.

[This message has been edited by ricreatr (edited 09-01-2024).]

quote Originally posted by ricreatr: Lot of threads about rear caliper pistons not retracting, this not that! Actually had brakes and park brake all working top notch and went to the track. (Waterford hills). Worked great first session, second session, pedal started dropping a ways. Fortunately noticed it before getting on the track. Finally noticed the left rear caliper piston retracting way too far after pumping brakes. Actually, watched the piston retract for five seconds. Ended up retracted a good 3/16, and bad enough the red brake light started flickering. Anybody see this before? I am about to take the caliper apart. Kinda hope to see a seal cooked or something like that.

I've encountered this on my s10 blazer. you have a leak in the caliper and master cylinder for the quick take-up system the fiero can be equipped with. our 88 ironically has thr opposite issue of staying in full contact randomly (something to do with the parking brake system I haven't quite figured out yet)

???

The piston would have to rotate in for it to retract out too far if it was working correctly prior. Now sure how or why it would do this.

Yeah, it seems weird there was no rotation. That set of pads had the nubs on the back to stop rotation.

I am digging way back in memory, the quick take up was for the drums, no? There are no external leaks. I need to see some diagrams.

Took the caliper apart. No cooked parts. Only problem was some gray sludge in there. Reassembled, and everything is working good. Think i will pull the other side and see what it looks like.