Yesterday, I was backing out of my garage and I heard what it sounded like a hydraulic gas release. In addition sometimes the vehicle has a hard time starting and I have a fully charged battery. I have almost 90k miles and this morning when I pushed the start button it wouldn't turn over and I got a warning on my cluster gauge it read "Service Electronic Brake System" and it started fine on the second try. However, this is the second time it has done this within the last 3 months and I am a bit concerned. I am not sure if the what it sounds like a hydraulic gas release once in a while (I've heard it twice as I was backing out of my garage so far) and I tried to pull codes but nothing came up. TIA!