Ej8_KiD

So im in the middle of upgrading to ITR calipers with 11.1" prelude rotors , ep3 rear calipers and rotos along with a 1" MC and booster , now i think i was sold a 00 prelude booster and MC for a 98+itr one.

Problem is the brake pedal is waaay too low and the car bearly breaks. i've bench bleed the mc and bleed the brakes a few times to make sure all the air is out of the system and nothing. i had to extend the booster vacuum line in order to reach the booster and manifold. if i put the line backwards ( with the arrow that says engine to the booster side )the car brakes but the pedal is low like i said , if i put the line the way its supposed to be the pedal goes all the way to the floor when the engine is on , with the car off i have pressure in the pedal , is this a bad booster o mc?

HOMEMADEPOWER

I had the same problem awhile back and i got a new booster and rebuild my brake master then my brakes worked properly after that.

Ej8_KiD

i got the old master and booster back in the car and i still have no pressure , i opened the bleeder screw on one of the calipers and fluid doesnt come out when i pump the pedal , i think the problem is the check valve , could this be?

Ej8_KiD

bump for some opinions

NVturbo

Make sure there the brake lines aren't cut. Does the fluid in the reservoir drain by itself?

Ej8_KiD

cut as in causing a leak? if thats what u mean then , no. the car has no leaks.

Ej8_KiD

Bled the system again , if the vacuum hose is connected the way its supposed to be with the arrow going to the engine the brakes have pressure while the car is off , once its on it has no pressure and when i let go of the pedal the idle goes up a few hundred rpms

if the vacuum hose is backwards the car stops but the pedal is really low and does not grip hard enough.

This is really driving me crazy.