Re: brake booster or master cylinder bad?
Ok, I got, the belt tensioner, idler pulley and new belt put on. No more squeeks from under the hood. The belt tensioner was the problem, it was tweaked outwards just enough to cut the belt. Anyway, all is fine now.
I check what you're talking about. The pedal does what its supposed to with engine off and then on. But still, when I go to brake suddenly, and push hard, it feels like something is failing...even if I don't pump the brakes like I mentioned before and just go hit the pedal hard, they don't want to stop and it can be scary. I bought a new remanufactered master cly and will replace I guess. I don't know what else it could be or how to diagnose anything else.
1999 Mercury Sable GS *Stock 3.0L, 2v