Has anyone else experienced this problem with their FC? When I put light pressure on the brake, it goes to the floor and loses almost all brake pressure. But if I give it a nice solid jab, the pedal's nice and solid no matter how little force I use. Whadafock?

 

Yes, I had the same problem in my FC. It will get worse. Have you noticed that it also gets worse as the engine gets to full operating temperature?

It's the seals inside the master cyl. They are wearing out and not sealing properly. When you press lightly, fluid gets around them. When you jab it, they flare out and seal, and the pressure holds them.

Anyway, it's time to replace or rebuild the master cyl. I recommend replace, because it doesn't cost much more and it's a lot less work.

 

That happened to me too. I have a working master cyl in my parts car, I hope it's easy to swap. I'm still learning about all that junk.