Every once in a while, I'll push my brake pedal down far enough to begin slowing the car down, but after a second or 2, the brakes seem to lose their effectiveness and I have to push the pedal a little further. Then another second or 2 and I have to push it even further. And further... This just started happening today, and my brake fluid is still at the max line with no sign of any leaks. What could the problem be? '91 CRX.

 

Jack the front tires off the ground and grab each wheel and shake it. Is there any play up-down or front-back?

 

Both wheels shake a bit due to a bad sway bar and wheel bearing on the driver's side, and the outer tie rod on the passengers side.

 

Check the tightness if your axle nut. Loosen it a few turns then tighten it bask down.