Thread: Brake Questions

I am having problems with my braking on my grand prix(2004 Pontiac Grand Prix GT2), these are the symptoms. I did not notice a puddle, I pressed the brake down to around half an inch of travel left. There was a little brake pressure, enough to slow the car down and stop. I filled the brake fluid reservoir, that did not fix the problem, i checked the reservoir and it still had fluid in it. Does anybody have any insights? Any help would be appreciated.

Was the resevoir empty or low to begin with? If so then you have a leak somewhere. Not sure if the 04's changed anything but the rear brake line on the 97-03's is routed through the rear subframe and is a known rust point to where the line will leak slowly and then it will just rupture. Ask me how I know, lol...

Another place to look is where the brake lines come up the drivers side of the firewall. Might be easier to see this from underneath.

If all lines are dry and you can find no external leak then I would think the master cylinder itself has failed.