Pontiac Forum - Pontiac Discussion Forums - 99 Grand Am, brake leak, ABS, trac light, etc.

My girlfriends 99 Grand Am decided that it was going to have braking issues yesterday night.

Symptoms:
-Very mushy brake pedal, still brakes okay but there is definitely some air in the system somewhere. Seems to brake fine but you really have to push on the pedal a lot more than usual. Happened more or less all of a sudden. Isn't getting noticeably worse though.
-ABS, Trac Off, and, briefly, the battery light all came on. After stopping and starting the car they would go off but come back within a minute or so.
-Had full brake fluid 4 weeks ago, checked it yesterday and it gone 1/4 of the way from MAX to MIN, not a huge amount.
-Checked all the lines, both front calipers, the brake pedal, and all around the master cylinder. No leaks that I can see. Put it in the garage and topped it off. After playing around with it for about 2 hours it had gone down a very tiny bit but still not a drop anywhere I could see.
-Bled the front two lines and topped it off, no change but the lights went away for about a 50 mile drive and then came back. Can't bleed the back cause I cant get a 8mm socket on the nut there (strut bolt in the way) and I don't have a 8mm wrench. Getting one tomorrow.

So, obviously I have a leak somewhere. My thoughts are the master cylinder or the ABS unit. I couldn't find the ABS unit though, where is it on the 99 grand am? Also, is there a special process for bleeding the 99 grand am cause I read online that some have to be bled at the ABS unit as well? It's still drivable but who knows for how long. Any advice?