Sudden brake failure

2002 saturn l200 brakes pedal has went to floortwice in the last 6
months after doing front pads. no leaks and did not open system.
Anyone else have this problem. I would normally change the master
cylinder. Its strange that the brake pedal is normal now.

Any ideas?

Thanks

 

how is the fluid level and color in the brake reservoir?
If the fluid is normal level and there are no visible leaks, I would flush
the old fluid out and replace it until fluid at all the bleed ports runs
clear.
Start with the right rear brake bleed port (furthest distance from master
cylinder), left rear, right front and lastly left front. Often times some
dirt or gunk interferes with master cylinder piston sealing. Sometimes you
get lucky and are able to flush out any schmutz otherwise the master
cylinder would have to be replaced.
If you have ABS, it is a flow through system and does not have to be
energized/cycled while bleeding the brakes.