Replaced pads and rotors, brake pedal sinking to floor now?!?

[lbv150]

The worst thing you can do is retract the caliper pistons with the bleeders closed...never send old fluid back up the system. Things happen to valves and ABS parts....

 

[UniqueTII]

The worst thing you can do is retract the caliper pistons with the bleeders closed...never send old fluid back up the system. Things happen to valves and ABS parts....

Yep, definitely won't be doing that anymore!

 

[UniqueTII]

I got a used ABS module that I just installed, programmed, and bled. No change in the pedal issue.

 

[Trainmaster]

Try crimping off the rear brake hose to further isolate the problem.

 

[07navi]

Crimp all around and get it narrowed down.

 

[nater]

Is there a Load sensing proportioning valve on the expy?

 

[UniqueTII]

Sorry for the slow response, I was out of town for a bit. We isolated the issue to the front by clamping lines a while back, but I'll do it again to see if anything changed!

 

[UniqueTII]

Crimping lines didn't change the behavior at all (with the old HCU it felt like it firmed up when both fronts were clamped). I swapped out a spare (used) master cylinder I had, bled it, then bled the system again using Forscan. No change in pedal behavior.

I'm thinking I may have to return the used HCU and grab a new one.

 

[Langer]

@UniqueTII any updates?

 

[UniqueTII]

I am throwing in the towel and taking it to a shop. I don't have enough time to keep messing with it.