when I press my brakes it is hard and sounds like air is escaping
Your power brake booster is shot, if you have quite a few miles on it you might consider replacing the entire master cylinder/booster assembly as a unit, might save you some trouble later. Don't forget to flush the entire system to get rid of any contaminants that might be in the fluid now. Hope this helps.
when I press my brakes it is hard and sounds like air is escaping what can i check to make sure that is the booster.
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