Brake Fade @ Traffic Light

OK, I just had a brake job including new fluid, car worked great for the 1st month, now the pedal sinks to the floor while I am at a traffic light, what gives? :banghead:
'99 Blazer ZR2

Take it back and have them re-bleed the brakes. If it still does it afterwards, the master cylinder may be bad. Either it would need a rebuild or replacement

If the pedal goes to the floor at a stoplight while your foot is on it, a very strong possibility is your master cylinder. It's an internal leak with no external fluid visibility; there might be some leakage from the backside where it goes into the booster but you can't see it. It's happened to me twice with other cars.

It sometimes happens when they push the caliper piston back into the bore for the new brakes. Since it happened to me, I always loosen the adjuster screw when I spread the piston back so there is no pressure back to the master cylinder.

Hope this helps.