I have a 1992 Olds 98. (3.8l, fwd) my brakes have been getting soft lately and I had the lines bled. They worked fine for a couple months then they went soft again. So I had the master cylinder replaced today and they still seem soft. Any ideas? The pads are good (I replaced them last year).
Air is getting into the brake system through the disc brake calipers or the rear brake wheel cylinders most likely. They probably need rebuilt or replaced.
If they firm up when you pump them a couple of times, air is almost certainly getting into the brake lines somehow (is the reservoir tank on the Master Cylinder full?). Perhaps they weren’t properly bled when the master cylinder was replaced?