Problem:
Intermittent Sinking pedal no sign of brake fluid loss. Strange situation where sometimes it sinks and sometimes its perfect for days.
Intermittent audible squeak when I push down the brake pedal.

Trouble shoot first:
1. Bleed brake fluid
2. Check for stuck caliper pins
3. Check brake pads


Tools:
Wiper puller
10mm socket
12mm socket
14mm socket
10mm open ended wrench
Pliars
Extensions
Master Brake Cylinder does not come with reservoir: $86 Advance Autoparts
DOT 3 Synthetic Brake Fluid
Bleeder kit (comes with autozone versino. not with advance auto parts version)
Shop towels
Liquid Wrench

Steps to replace Master Brake Cylinder
1. First remove wipers. If stuck use wiper puller $11 at advance auto to remove the passenger wiper. If driver wiper stuck wiper puller will not work. Must work around it and remove wiper with assembly and cowel in one shot.

2. Remove wiper cowel (black flat part under wiper)

3. Remove Wiper Pan. You have to take out 2 bolts on each side of the shock assembly. Use liquid wrench if stuck. There are a few 10mm bolts holding the pan to the frame. Easy to get out.

4. Remove top part of air box. My pictures show I removed alot more because I was doing my valve cover at the time.

5. Drain Brake reservoir

6. Remove spring clips holding rubber hoses

7. Remove the two brake lines with 10mm open ended wrench. Be sure to put down shop towels to catch old brake fluid

8. Remove 2 10mm bolts holding the master brake cylinder

9. Be careful not to loose that small flat piece on the left side. It falls out as soon as you remove the 10mm

10. The master cylinder should be able to be pulled out. Wiggle it out.

11. You may have received a "jig" with instructions. Use it to confirm the distance of the piston in the brake booster is in the right position. Mine was where it was suppose to be but confirmed with the jig.

12. Install new master brake cylinder using the 2 10mm bolts

13. Bleed the master cylinder while on the car before reinstalling brake lines

14. Reinstall the 2 brake lines. Do not over tighten

15. Replace Rubber hoses making sure the retainer clips are in the right position the hold the hoses in place

16. Refill reservoir

17. Bleed the brakes at the caliper. (starting with rear passenger then rear driver then passenger then driver side)

18. Reinstall wiper assembly in reverse order

19. Test Drive

19. Enjoy that $745 you just saved buy doing it yourself.