Another cause for spongy brake pedal
 

I just discovered why I had a spongy feeling pedal after changing the pads. On the rear pads there is a small pin that protrudes and the piston must be rotated so that the relieved area on the piston will clear the pin on the inside pad. The Haynes manual mentions this but the workshop manual does not!
The pistons were hitting the pins rather than the back of the pads on both of my rear calipers. This causes very uneven pressure on the pads.

The may be common knowledge but I have been doing my own brake jobs for 35 years and never ran into this before.

One more thing to check!:D
I never noticed that difference between the FSM and Haynes. The again, I don't think I've done my rears yet.

oh man, I need to check this. I hope this is my problem. ;)

you should have shims on the back of the pads. if they're rusty in anyway, shape of form, they can cause that vague feeling.

I was just gonna say, "wouldnt those shims cover up this pin?"

yeah, and if they're totally not there, .......well then there you go. they're cheap too.

yeah, but for what you get, it's kind of like uhhh...

well, at least for me... i got the hardware kit from mazdatrix that included the shims for the fronts and one pin, the one that goes from one of the pins that holds the pads in to the other... almost 30 bucks!

shims, M clips, plated brass sliders full rear kit $45 Canadian from Mazda.. Picked up a replacement set yesterday.