My clutch pedal would depress with no pressure and w/o activating the clutch. I read that there might be air in the master cylinder, so I bled it out and it worked fine for a few days. Then, it went out again, so I was going to bleed it again in order to drive it to the shop. I replaced a worn clutch hose and tried to bleed it again, but now no pressure will build after bleeding. Can anyone tell me why this is happening?