Well, thanks for the help and advice guys.

I went home yesterday and changed the relays, fuses, and the pressure switch (Luckily one of my buddies gave me new ones about a year ago and I kept them in case of an emergency, so I didn't have to spend a dime doing this) and it still did the same thing. I also checked the proportioning valve and that was ok.  All the wires were hooked up ok and the unit was running.

So, I had a spare unit my buddy also gave me.  I got so frustrated I went to my dad's house and suprisingly it took us 2.5 hours to do the job.  :D

Now, I don't think we bled the unit right because this is what happens.  Car brakes ok but when you brake too hard/fast the brake pedal goes down a bit and then comes back up by itself.  The BRAKE light also comes on when you hit the brake pedal.  Theres no easy way to explain this but that's the best I can do.  Is this a bad unit also or are my suspicions correct and I didn't bleed the unit correctly?

Thanks for any help you can supply.

Ok. so I'm driving with no problems on Friday when I go to stop at a red light and the brake pedal gets really hard and it gets hard to stop. I went home and this is what I've figured out so far. Both front brakes are working but both rear aren't. I disconnected the brake fluid hose off the rear calipers and they aren't getting any brake fluid. Can this be the rear brake relay? What exactly does the relay work for? Is it the master cylinder again?  Someone told me it could be the ?proportioning valve?, i'm not sure exactly what it is but what do you guys think.

Please help guys..I'm kinda stomped. :roll: