vmolla1

I have a 98 civic... Doin rear disk conversion... Everything brand new pads rotors calipers braided brake lines proportioning valve off a civic si and brand new master... Bleed the brakes and pedal feels good intill i turn on the car and it drops right to the floor... I released the vacumm hose from booster and pedal is fine while car runs... Any help please...

2000EKCoupe

you probably have a bad booster man, or i believe there is a check valve in that hose that goes from the booster to the intake manifold

racerx510

did you bleed it right? i think its LR, RF, RR, LF left=driver side. its either that or reverse it RR, LF, LR, RF

jbpnoman

Bleeding wouldn't cause the brakes to drop when the car is on. Your brake booster is shot.

CX-Adam

I'll repeat what everyone else is saying. It's your brake booster. The same exact thing happened to me. I replaced the brake booster. Problem solved.

nealnanoHX

You dont need the prop valve on 96+, all share the same prop valve. You want to bleed the brakes starting with the brake farthest away from the master cylinder so start at the right rear, then left rear, right front last left front. Yea it sounds like a bad booster or it could be a blown master cylinder.

vmolla1

Thanks guys... the booster is the only part that is not new... So ill try that