No fluid to one front and one rear brake

It sounds like there is some other problem. Bleeding the brakes is not the solution. That is done when repairs result in having air in the system. The most common cause of this problem is improper bleeding procedures. Specifically, the brake pedal was pushed all the way to the floor. Crud and corrosion build up in the lower halves of the bores where the pistons in the master cylinder do not normally travel. Pushing the brake pedal over half way to the floor runs the rubber lip seals over that crud and can rip them. That results in a slowly-sinking brake pedal, and that often does not show up until two or three days later.

There is another problem that only applies to GM front-wheel-drive cars. There is a valve that trips in the master cylinder when unequal pressures build up in the two halves of the system. That valve prevents loss of brake fluid if there is a leak, and that is what happens when pedal-bleeding with a helper. That valve blocks fluid flow to one front wheel and the opposite rear wheel. That is what you have.

The only way I have ever found to reset that valve is to loosen the cap on the brake fluid reservoir, open the bleeder screw for one of the wheels that is not flowing any fluid, then give that bleeder screw a quick, short burst of compressed air. Do not go overboard. You would like to avoid pushing air all the way up to the master cylinder. Once the valve is unseated, just allow those two wheels to gravity-bleed. When the air bubbles stop appearing, close the bleeder screw, then push the brake pedal a few times, but never push it more than half way to the floor. Open each bleeder once more to expel the last few remaining air bubbles.

Normally you need a burst of higher pressure air than what a can will do.

You're welcome.

Hi guys. I use a rubber-tipped air nozzle, although the more common regular steel kind works just as well. The seal to the opened bleeder screw doesn't have to be anywhere near perfect.

To avoid having to bleed a lot of air back out, I hold the nozzle to the bleeder screw, then with my other hand, I give the handle one quick slap with the side of my palm. That gives a blast for just a fraction of a second, and the air can be bled back out in about 10 to 15 seconds.

Once that valve is reset and fluid drips from all the wheels, let it just gravity-bleed like that until you don't see any more air bubbles coming out. Close those bleeder screws, then "irritate" the brake pedal by hand. Stroke it an inch or two to wash any remaining air bubbles into the calipers and wheel cylinders. Open each bleeder screw once more to expel those couple of bubbles.

We rarely resort to pedal-bleeding any more. If the calipers were replaced or rebuilt, or even if the pistons were just pressed in to make room for new, thicker pads, those pistons have to be run back out to adjust them as the last step in the service. That is done by pumping the brake pedal a few times. This is another time that valve in the master cylinder can be tripped. To prevent that, be sure to never push the brake pedal more than halfway to the floor.

If they are nice and hard with the engine off but soft with it running it could be the booster. A quick way to tell if it's something else is to pop the vacuum line off the booster and plug it so you don't cause an intake leak and see how they act without the booster connected, that would eliminate it from the system for testing. If they still work good and the pedal feels solid then you have your answer. Just be careful as most vehicles built then can take some solid leg pressure to stop without the booster assisting.

The idea is to get the booster out of the circuit just to be sure it isn't anything in the ABS module. If the brakes work with a good pedal with the booster disconnected it's likely the booster. If they still feel mushy with it disconnected the problem is something else. It's just a faster way to test than swapping the booster only to find it doesn't help. Also be sure to watch the rubber hoses before you start testing, a failed hose that is expanding under pressure could also cause a mushy pedal. Something that gets overlooked if they look good.