Hey guys, I've searched and tried every suggestion and I'm at a loss so here we go.

When I got my Civic the brake pedal would go straight to the floor when trying to brake. Everything I've read said that typically is the master cylinder or simply air in the lines. So first I bled the brakes. Didn't fix it. Bled them again just in case, nada. Picked up a reman master cylinder, bench bled, bled the brakes again, pedal still goes to the floor. Figured I would try returning the master cylinder and getting a brand new one just in case the mc was bad, nope. Installed the new one and bled the brakes again and still have a soft pedal.

So I went on to checking the vacuum lines. Pulled the lines with the car on and they have vacuum. After driving up and down the block a few times attempting to brake, I turned it off, let it set for 5 minutes and pulled the vacuum line again and air wooshed out so there was still pressure there.

Now I'm just sitting in the driveway banging my head up against the steering wheel. Help! Thanks guys.

 

No brake fluid leak anywhere, like from the rear wheel cylinders?

Also, what is your method of bleeding?

 

I think your brake booster is bad. I have also seen this with proportioning valves being plugged.

 

No fluid leaks.

I have my wife pumping the brake while Ive loosened each bleeder screw starting with right rear, left rear, right front, left front.

 

Where is the prop valve? Are there any other tests I can do to verify it's the booster? Thanks

 

When she is pumping, does the brake pedal get hard for her?


I just realized how dirty that sounded.

btw, your wife gets the wife-of-the-year award for this ****. Pumping brakes on a hooty-EF ain't exactly glamorous.

 

Haha yea a little dirty and yea she's awesome.

She said it felt like it was getting harder with each pump.

 

If the pedal isn't getting hard when she pumps it, like hard enough where she can't push it all the way to the floor, then there is an air leak somewhere or the master cylinder still has air in it. You might have to take it back off and bench-bleed it again. That air won't come out any other way.

 

If the prop valve was clogged wouldn't that have hindered my bleeding of the brakes?

 

I'll try bench bleeding again. When bleeding the brakes, should my wife put the pedal all the way to the floor to pump? I was told to put a small piece of wood behind it to avoid going to the floor. Thanks again guys.

 

passenger side engine bay next to your strut mounts. below your fuse box

 

Did you make progress, Eric? All the way to the floor is what you want. The first couple of strokes will require you to pull the pedal back up, but it should build up pressure pretty quickly. Make sure the brake fluid level never dips out of the reservoir. That'll just put air right back into the master cylinder.

 

I'll be doing it tonight when I get off work. I'll let you know how it turns out. Thanks again!

 

Im feeling prop valve as well. Almost the only culprit after all youve done/checked. When pressure is applied is it pulling one way or another?

 

Ok so I bled the brakes again. Had a friend help to make sure I did everything correctly. Problem still remains. So prop valve or booster is the next step?

 

I haven't noticed any pulling while braking.

 

So I've now changed the rear shoes and wheel cylinders as well. Shoes were shot and cylinders were leaking. Still have a soft pedal.

 

I guess you are down to the booster and prop valve, then. I've never replaced one of those, so I can't help you there. Sorry. I still can't think how a booster would cause this, but I'm not a pro.

You'll have an entirely new brake system when you're done. This is probably why the guy sold it.

 

Seems that way. Is one more likely than the other?

 

How much fluid was coming out when you were bleeding the brakes?

 

There was a good amount of fluid coming out of all four corners.

 

I'd guess booster. If you have good flow out of every corner, the prop valve can't be clogged.

 

If you're still in Bend, pm me. I'll at least stop by to take a look.