Hi. I have a 2002 Honda Civic EX 1.7L. Recently the brake pedal would sometimes go to the floor when I'd apply the brakes. The car would still stop, but not as quickly as normally. If I apply the brake and it goes to the floor I would release the pedal and reapply the brake and it would stop at it's normal position and the brakes felt firm and the car would stop fine.
I was told my problem was the master cylinder so I bought one on Sunday and replaced it. I bled the lines and it seemed like all the air was out. The brakes worked great and the pedal stopped in the same place and was firm. Now today on my way to work the pedal went down a little farther than normal during one stop. On the way home it stopped in different places. The brakes would always grab and the pedal felt fairly firm wherever it stopped. I drove it this evening again and the pedal went to the floor like with the old master cylinder. One pump and they grabbed in the normal spot.
Any ideas of what is going on? Did I not bleed the lines well enough? Is the new master cylinder just junk? I saw in the manual that air can get trapped in the ABS sensor, but an air bubble problem should just make the pedal squishy, not change where it grabs, right? I'm stumped and I really don't want to take my car in if I can fix it.