Ok well the end of summer I started having a problem braking. When I go WOT for more than a few seconds then let off I pretty much have no pressure in my brakes. The pedal will push to the floor and nothing, then after a few seconds they slowly come back. When it first happened it was like the hottest day of the year soo I thought they got heatsoaked but it kept happening. I bled the brakes properly and the rear wheel cylinder isnt leaking soo not realy sure. Does it sound like the master cylinder? The fluid level is always fine as well. I have some braided brake lines to put on but I realy doubt its a problem with the factory rubber lines expanding. I have also checked the brake booster for leaks and its ok.

It only realy happens when I go full throttle for more than a few seconds, like a quarter mile pass. The longer I stay full throttle the worse it is and the longer it takes for the pedal to get some feel in it. Brakes are stock except for drilled/slotted rotors and hawk pads. Any ideas?

i'll say master cylinder! are the calipers working correctly?




WiGM-Tuners member.

Yep calipers are fine. Why the master cylinder? The valve in it?

What happens when you have no pedal and you rapidly pump your brakes? Do you get them back right away?

The only relationship between the motor and the brakes is the vacuum booster. The booster only makes pushing the pedal easier, not if the brakes work or not.

Soft brake hoses can cause funny or bad braking. Air in the line can cause bad braking, a bypassing master cylinder can cause bad braking.

Are you using any brake fluid? IF so, how much.

Stupid question but do you have fluid in your brake reservoir?

Dave