[Bubbajet]

When I get in and start the car, sometimes the brake pedal is nice and soft like I'd expect, sometimes it's hard as a rock like they've been pumped up, like someone sat in the car and mashed on the brakes over and over. When it's hard, I have to press quite hard to get the car to start, occasionally ridiculously hard.

Seems like the pumped up version is during shorter down times, maybe.

Anyone else seeing this?

 

[Nai3t]

Not exactly what you're experiencing, but I noticed the brake pedal move on its own, maybe about an inch, when either opening or closing the door (I don't remember exactly which). So yeah, there's some behind the curtain magic happening there.

 

[surprising]

Yes I've noticed this several times now. I haven't really paid attention to when it occurs but it's the same as the OP described - brake pedal is hard to press and requires a bit more force to start the car. Once car is started, the pedal pressure is alleviated and all is normal.

 

[ChristophW]

My impression is that it's part of the start-up process. Short travel, firm resistance = car sleeps, longer travel, much softer feel = car has woken up. If your door closing seems to be part of the picture it is perhaps just the sequence of things you do when entering and starting.

 

[Huey52]

Also often part of the startup process appears to be the computer checking to see if the wiper blades are in the raised "service" or normal position, as often a slight movement.
Many things going on so I just sit for a bit and let it all happen before hitting the brakes (which for me too are sometimes firm and other times detent-movement) and thereafter waiting a bit before switching the 'transmission.'