help?? brake issues
 

Hey, im new to the forum but I have a few brake questions. I have a 98 civic lx. The brake pedal was really hard to press and the car didn't stop well, so I replaced front rotors, front pads, rear drums, rear shoes and then I bled the front brake lines. The brakes are much better but the car still doesn't seem right. When I brake the slows down but feels like the pedal goes to the floor, other times it will lock the brakes up at 40mph. When I repeatedly step on the brake it will be a normal pedal then a very low pedal. The fluid is full and the rear brakes are fully adjusted, and nothing is leaking.

Any suggestions?

Master cylinder??

Thanks Bill

i would look into the brake booster.also if you accidentally introduced air into the brake system when you bled them that could make the brakes unresponsive and spongey. what kind of fluid did you use ???