CX-9 brake booster is bad?

Hey all.
When slowing down the cx9,I feel the brake pedal will not return to its original position after being pressed.
Have you ever experienced this issue and if the mazda cx9 brake booster is bad ?
I was wondering if this mazda cx 9 brake booster replacement would work on a 08 mazda cx-9 ?
Any help would be greatly appreciated
I just replaced my booster on my 13, my issue was much more noticeable when reversing. It wasn't so much the pedal not returning, but it just wouldn't stop.

Do your brakes work ok/better while the car is at speed vs from a stop/parked/low speed?

I'd check your brake fluid too. Low fluid could affect the position of your pedal, as well as amount of wear on your pads.
2011 CX-9 GT AWD
Hello everyone, I did not want to open another title and decided to continue here.

I replaced the brake booster on 2011 CX-9. It took a long time to remove it out and install the new one. I filled the reservoir and bled the air. Brake works fine. I adjusted the brake switch also.

I do not know what is the part name between pedal to brake switch. It is black box. When I open it, a white plastic part with spring came out. I tried to reinstall it but all I had some issues. I attempted to install it, I couldn't turn off the ignition. Tried a different way, gear knob moved without brake pedal. One time it worked fine but it locked the gear knob.

I removed it now and it works fine.

What is this part called? Any idea how I can install the white plastic part in it? Plastic part is held on with a cable and it makes something in the box. No white plastic showing in picture.


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