When I press down on the brake pedal, it slowly sinks to the floor, but I have no visible leaks around the car.

Would this likely be the master cylinder leaking internally?

If so, where is a good place to buy one for less than the crazy $600 the dealer wants. Mine is the 4 bolts from the booster to the firewall model.

Thanks in advance.

 

bled the brakes recently?

 

Yes, just bled them, re-bled them. You are correct, this was noticed after bleeding the brakes.

I just did a pad slap with akebono pads.

Is it that simple, just air still in the lines somewhere??

That does make sense. I think what may have happened was that I put the pedal to the floor and while holding, my "assistant" then tightened, instead of while the fluid was squirting out.

I'll bleed them again "properly" and see if I can get it fixed.

At least this is the cheapest possible fix.

The only problem I see is "you can't fix stupid"...

 

no one believed me at first but it's a simple fix - I spent 3 days asking on here a few years ago.
The answer isn't a new MC you've got air in the front calipers, if they're standard, if Brembo's then that's another story.

Unbolt the caliper and hang it with the bleed nipple pointed directly up, now follow your standard pump, nip after the bubbles and the fluid runs clear.

Simple, and I expect a thanks as a new MC is $1,000+

 

It took a while, but wife is a pro at "pump,pump,pump, hold!" As she yells "holding!" I pop the bleeder, and we do it over and over until there is no more spitting. A bitch but beats the ^^^^ out of bad brakes or new MC. Haven't tried Sean's way (but I have a lot of sweat equity in training!).