Brake booster filter vacuum leak (Page 2/2) theogre JAN 08, 07:35 PM quote Originally posted by Spadesluck: Food for thought.....has anyone reported any Fiero brake booster going out and destroying the motor with debris? "Bad" Boosters etc often don't destroy engines right away but junk from them scratches cyl bores, blocks valve(s) & start to burn them, & other problems often not counted as a root cause by most. Is mainly rust & other crap sitting in the steel pipe that's going to slug the engine w/ it if have a leak in that part of car. Rust/crap in the booster can hurt too but have to stir that up then get enough air to line check valve. Most booster fails don't have huge vac leaks because fails are diaphragm(s) or control valve. But plastic check valve can break or line pulls off then have a huge leak. Note: Many think the line end is just a fitting/adapter to fit hose to the booster... Inside is a sprung Check valve that can have other problems causing poor or no booster performance sim to bad booster. This valve can be Replace w/o buying a new booster.