Well, the brakes on my integra have been acting odd. Symptoms are that of a leaky master cylinder: Pedal will drop to the floor. But it isn't consistent, and so this kind of freaks me out a bit; and I wonder if there may be other problems. I used Valvoline synthetic Dot 3/Dot 4 brake fluid, and was wondering if the fact that it is a synthetic may have any effect on the performance, or if you think it is just an intermitently failing master cylinder seal. I am just confused because it is so inconsistent. The sinking pedal happens most often when it's hot outside, or when I am on an incline facing downhill, but like I said, it doesn't happen all the time. Here is a picture of the bottle of fluid I am running. Anybody had these intermittent problems? I'm hoping to do the legend brakes upgrade next month if I can source in expensive parts.