Hi, I haven't used my Buick for 10 months and decided to give it a test today (start it and pump the brakes a bit). When I pressed the brake it went slowly to the floor, and only returned slightly. Then when I revved the accelerator it moved with the revs. So I checked the master cylinder (this car has power brakes btw) and there was basically no fluid, just a dribble. So I filled it up, but I cannot understand why the brake fluid disappeared within 10 months, and I can't see any leaks. Also, would this cause any problems now that I've pumped the brakes with no fluid in around the system. Cheers Andy.