Just bought this vehicle and while sitting at light noticed the pedal slowlllllly sinking. Found no leaks and like everyone else on the Internet I figured it was a mastercylinder car has 120k on it, well taken care of. So I put a master cylinder on it and figured it may be due for a complete flush anyways so what the heck. Unfortunately....that fixed nothing! The problem is still there exactly as before! It does eventually get to a point where it quits sinking that is not all the way to the floor but a whole lot of travel to get there! This is an EX model with discs at all four corners. My first impression of the problem was like back in the day where your rear drums might have shoes that are way out of adjustment and the pedal was simply sinking as it filled the rear wheel cylinders. Being that this has 4 wheel disks, that is certainly not going on so the idea of the mastercylinder internally leaking within itself was surely possible. No loss of fluid anywhere. So what can I look to next?

Just in case anyone else has this proble, I read some threads that talked about the ABS in the scope of things. I took a chance and found a gravel rd and stomped on the brakes to get the ABS to kick in. I did this about 4 or 5 times and don’t ask me why but it cured my sinking brake pedal! Each time I did it I got an improvement. If I read properly engaging the ABS will chase any air out of that system. No clue how it works but hate that I did all the work swapping the MC and full flush when in fact all I had to do was make the ABS function. Go figure. All good.