Why is the brake petal soft on your 93 Toyota 4Runner after you changed the brake pads?

You need to bleed the brakes. Loosen the bleeder valve on one of the calipers and have someone press and hold the brake pedal. Tighten the valve and release the brake pedal. (If you let off of the pedal with the valve loose, air will be drawn into the system and make the problem worse.)