Why do my brakes feel soft and go down to the floor when i apply light pressure but work normal if i get on them hard? I accidently put power steering fluid in when i had a constant leak that i fixed about 3 months later but i think that most of it may not of leaked out so i removed the back lines and pumped it a few times but it still wont work right.

Your better off going by the feel of the pedal rather than measurements. Try this. With the engine off and the brake system cold remove the key from the ignition and pump the brake pedal. it should get progressively harder and your foot travels a shorter and shorter distance until its too hard to press.
Press and hold the brake pedal hard down then start the engine. You should feel the pedal soften, that's the vacuum inside the brake booster kicking in.
Release the pedal and again press it hard down, holding it there. The pedal should feel firm and not change. Release and repeat to make sure.
If the pedal has no resistance check your work as there is no pressure in the system. If the pedal is soft or spongey re-bleed the system starting with the calliper furthest away from the reservoir.

first replace master cylinder the replace rear wheel brake cylinders.. Inspect front pads for non uniform wear, inspect front rotors replace if badly worn or scarred. You are dealing with 23-24 year old parts.

You have air trapped in the braking system somewhere. Have you bled the system thoroughly at all four wheels?
Have you changed the front calipers recently. Many years ago, I helped a friend mount new calipers on his vehicle, and we put the new calipers on the wrong side -- right one on the left side and vice versa. In this configuration, the bleeder screw wound up on the lower portion of the caliper instead of at the top, where it needs to be to allow trapped air to come out. Just a thought.

This is the usual behavior. When the engine is running, it is generating a vacuum, which pulls on a diaphragm in the brake booster. This is what is called "power brakes". It uses engine vacuum to help push hydraulic fluid thus reducing the amount of pressure you must apply to the brake pedal. When the engine is off your foot has to make up for the force that engine vacuum usually applies, which makes the pedal feel much more firm.

to test your brake assist is working. stop the motor. Press w few times the brakes, till the pedal feels sturdy. Then while pressing the pedal down firmly, start the engine. When you feel the pedal going down, like feeling "soft" you know the brake assist works. If nothing changes it is defect.

check cylinder brake

There is never a test or reason to pump your brakes

Accomplishes absolutely nothing.

There is no pressure in a braking system at all,
until you SLOWLY apply the brake pedal.

Then less than 1" off movement in the master cyl,
will develop 600 to 1800 lbs at the wheels

Release the brake pedal, the system goes to zero,
IT DOES NOT HOLD ANY PRESSURE

To answer your question

You not suppost to press the pedal hard
The saying goes--you apply the brakes,
not force the pedal arm and pin into the
vacuum booster, as though you want to damage it

When your driving what happens ?
You have higher manifold vacuum and
thus your pedal is normal,why the VACUUM
brake booster

hi from the uk have had this problem on a customers car b4 who had replaced frot calipers and pads and pedal went to floor on inspection of caliper i found that the steel spring clip that fits into two holes in the front face of caliper and must also locate behind the caliper carrierbehind two lugs was fitted incorrectly it had been fitted behind the outer pad resulting in when brake pedal off ?the caliper being floating type as it is known because it is fixed by two screw pins/bolts and moves on these pins/bolts as pads wear ? what happens is the spring fitted wrongly ? actually pushes against the outer pad and as a result the caliper piston is pushed back into its cylinder slightly as it moves on the locating pins/bolts resulting in pedal going to floor on 1st application but if pumped ? some brake pedal force is felt but is lost again when pedal released ? so try this ? remove the steel clips from both front calipers that retain caliper to carriers then press brake/pump pedal ? if as suggested above works? your pedal should pump up and remain ok when you release and still be firm when re applied ? all above is what i found on ford ford but many other models use similar calipers and spring locating recheck how this spring should locate hope this helps ? good luck

You have to bleed it on all 4 wheel

Well this is very serious I hope you deal with it right away. You mentioned that sometimes the pedal was hard,do you mean that its all the way up and it doesnt feel like you have power brakes?? If so have you noticed any sounds like air escaping (swoosh sound when brakes applied)? Failure of the power booster causes pedal to become very hard and could possibly be your problem for hard pedal if I understood you correctly. check to make sure that vacuum to the booster is conected properly and hose not kinked..Now for the solution for the pedal fading to the floor... You either have air in your brake system, A bypassing master cylinder , or a hydraulic leak...Were your brakes serviced recently?? if so try bleeding your brake system first...That would be the first step if still the problem persist I would isolate exactly where the problem was coming from.. To do this you would start at the passenger rear wheel and line clamp the brake hose to make that part of your brake sytem inoperable...when clamped try your brakes and note if brakes improved or had know affect on system (when testing obviously im not suggesting you drive to determine results of test procedure)repeat test for each wheel you have isolated the problem when brakes feel normal with one wheel clamped,which ever it may be.. This isnt as hard as it might soun and if you are confused at all dont hesitate to ask questions... Remember the only dumb question is the one you fail to ask I would hate for you to get into an accident ... Good luck!!!