I'll been noticing when starting my 06 GT after it sits for several hours or overnight, that the brake pedal is rock hard. I've got a manual so the first thing I do before I start the engine is press on the brake and then the clutch. Lately the brake pedal is rock hard with no movement when I first touch it. It hasn't always been this way. I had this same problem on my Probe GT and the brake booster had a leak in the diaphragm. Does this sound like the right diagnosis?
In the span of 2 weeks I've had three problems come up. It makes me worried when the warranty expires.
_____________________________
Steeda CAI&UDP/Bama Tune/FRPP 4.10 Steeda Sport Springs & HD Strut Mounts / D-Specs 2006 GT - 13.37@105.8
Mine does this too. I thought it was supposed to do that though because if you pump the brake a few times before starting it will harden up, then the second you turn it on it will release.
In this case I am not pumping the brake. It is hard the first time I touch it after parking. I''m making sure that I''m not discharging the vacuum when leaving the car. If I return within 1-3 hours, the pedal is still soft. After 4+ hours, it is hard.
_____________________________
Steeda CAI&UDP/Bama Tune/FRPP 4.10 Steeda Sport Springs & HD Strut Mounts / D-Specs 2006 GT - 13.37@105.8
Hmm...Never noticed this. To be honest, all I do when I start the car is put the gearbox in neutral, push in the clutch, and start the car. I''ll try to remember to feel the brake before I start the car when I get done with work.
Printable Version
Hard Brake Pedal after parking, brake booster leaking? - 
