My 2007 es 350 had the exact same issue. Stiff brake pedal. Most times it would start however it began to worsen and take 3 or 4 times before it would turn over. I just purchased a 2014 es 350 and after a week of driving it I have the experienced this again. On the tenth day of driving it wouldn't start! Its back in the dealership for a week now and they haven't duplicated the problem. By the way, they finally replaced the brake booster in my 2007. If anyone else has information, I would appreciate it. I am not happy to be dealing with this again
