Brake pressure problem

[Irnstlgld]

I have a 01 Camry that has had a soft brake peddle for a while. After bleeding the brakes and still having the soft peddle, I had a mechanic check it out. They said it was a bad master cylinder.
Well, I just changed the master cylinder and still have the same problem. I bench bleed the master cylinder and bleed all the lines once installed.
I went back to each brake line and noticed there was hardly any pressure at the front driver side and the rear passenger side brakes. The front passenger and rear driver had great pressure. I went a checked the master cylinder and the front out put was good, but the middle one at the double split was not.
What gives?

[73sport]

You didn't mention this and the descritiption says no, but warped rotors push the pads away and make the pedal soft but only feel this way when driving. When parked, you push it twice and it firms up once the pads seat on the rotors.

Have you inspected the brake lines? Rubber lines will buldge and fail. Have someone depress the pedal while you inspect them.

This car has ABS yes? That system could have an issue too.

[Irnstlgld]

Yes ABS on board. The 01 Camry LE 4cyl is still giving me problems with air in the bake lines. Haven't been able to drive the car for days.
Ever since I installed the new master cylinder all I get is air. Bench bleed the MC and installed it. Been doing the 2 man method for hours and no change. So I switched over to Mityvac - Vacuum Pump and still get lots of air out of each wheel. Spent over an hour on one wheel and nothing but air coming out.
I have seen a number of post say that the new MC could be bad and this is common. So I ordered another MC and will put it in tomorrow.
I would like to know if there is anything else that could be causing all the air. All the connections are tight and no signs of leaking.
Any thoughts?

[73sport]

So it totally got worse after MC install/replacement?

You may not be getting a full metered charge if the MC is not returning all the way. The rod that pushes the MC; can you pull the bolts and lines and confirm the rod is not depressing the MC when the nuts are tightened? Toyota spec says Zero clearance. But a few thousandths is better than depressed.

Shove some clay into the hole where the rod depresses the piston, install the MC, seating it completely. Remove it and inpsect the clay. If the clay is gone in the middle it means you have no clearance. Tighten the adjuster nut to shorten the rod. Try again. You don't want the piston depressed when the bolts are tight.

If the MC were slightly depressed and you pulled a vaccum at the wheel, it would not be able to pull fluid from the MC and it would make lots of bubbles.

Yes, you can get bad MC. Did it bench blead OK. Did you use hoses to recirculate or just pump it out to the ground?