I hear air when I pump my brakes after I just changed them on 2003 Hyundai XG350

just changed the back drivers side brake pad and now I can hear air when I pump them and they are still a little soft?

Asked by for the 2003 Hyundai XG350
I don't have much information from your question so here are some ideas for you. It's a little unclear which brake pads you replaced. Sounds like you didn't replace a set but only the left rear brake. I recommend replacing a complete set on the front or rear but not just one wheel. Also, when replacing pads, it's a good practice to replace or machine the rotors so that the discs run true and the pads break in properly.
If you didn't machine or replace the rotors, then the pads may not brake in properly and will give you a feeling of soft brakes. If you bled the brakes, maybe you got air into the lines and that's why they're soft. The 'air' sound could be due to the power booster having to do too much work assisting the brake system because of pad problems causing you to need to press unusually hard on the pedal. Just a guess.
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