Brakes Go to the Floor only when Tuning

So recently I was driving and my brakes would just go the floor when going into a turn.

I replaced my master cylinder, bench bled that and problem still persists.

I bled all the calipers twice, and the problem is still there.

When turning, the lines are not being touched, rubbed, etc...

It's wierd, because they will go the floor only on turns. Then you pump them a few times and they are back. I've read though a few other forums, and apparently this problems occurs very rarely. From other posts, people are saying it's either a brake booster or a "proportioning valve".

Just trying to get some insight on this

to test the brake booster have the car off and pump the brakes. if it gets really stiff then your booster is fine. the proportional valve controls the ratio to the front and rear brakes. if you have abs then you dont have a proportional valve. check the brake hoses at all 4 wheels and see if any of them are wet or swollen

^ This is not a brake booster issue. If it were, the pedal would be stiff at any moment. Also, he does have a proportionning valve... ABS doesn't change anything about that.

i think i might have a v6 proportioning valve laying around somewhere from my parts car, it was like some metal block that a bunch of lines went to

6 lines, 2 master, each wheel.

but it sounds like a mysterious problem, hydraulics are not compressible, you can never push that pedal down. do it front wheels off the ground (lets ya turn easy). make 'pressure stop tools' to replace ckts, then you know which is dead. go to parts store, buy cheap line with the correct fitting!!!!!! you can twist the line, I went fancy w/ solder.

can it happen when just turning the wheel or is it only when cornering?

Check the fittings, check the line for places it's getting rubbed or pinched. Look for brake fluid/fluid residue. If you can, jack it up and turn the wheels one way, then inspect the brake assembly. Do this on both sides. Must be something out of whack...

kn0x47 said:

to test the brake booster have the car off and pump the brakes. if it gets really stiff then your booster is fine. the proportional valve controls the ratio to the front and rear brakes. if you have abs then you dont have a proportional valve. check the brake hoses at all 4 wheels and see if any of them are wet or swollen

Click to expand...

No wet or swollen lines. The pedal gets stiff when the car is off

Brad2274 said:

i think i might have a v6 proportioning valve laying around somewhere from my parts car, it was like some metal block that a bunch of lines went to

Click to expand...

I'd like to see a picture if at all possible

xci.ed6 said:

6 lines, 2 master, each wheel.

but it sounds like a mysterious problem, hydraulics are not compressible, you can never push that pedal down. do it front wheels off the ground (lets ya turn easy). make 'pressure stop tools' to replace ckts, then you know which is dead. go to parts store, buy cheap line with the correct fitting!!!!!! you can twist the line, I went fancy w/ solder.

Click to expand...

So what you're saying is get it in the air, turn the wheels to check. What do you mean by "make pressure stop tools"

Brad2274 said:

can it happen when just turning the wheel or is it only when cornering?

Click to expand...

When you turn the wheel at all, barely moving or moving at like 30 or so

RedRyder said:

Check the fittings, check the line for places it's getting rubbed or pinched. Look for brake fluid/fluid residue. If you can, jack it up and turn the wheels one way, then inspect the brake assembly. Do this on both sides. Must be something out of whack...

Click to expand...

Fittings are fine, lines are not being pinched, no fluid leaking.

I need to get this figured out

line stop is like a plug, stops fluid out, air in.

Have you done any suspension work lately?