yes, but the pedal can be perfect with the car off, and as soon as you start the car, it could sink to the floor again and not work at all.

 

yes, thats what im saying. IF it acts fine with the car off, but not with it running, it's probably a bad booster.

 

If it does, then theres you problem!

 

leave the car off, pump the brakes till it gets rock hard, once it's rock hard let off of it for 10 seconds, press it again. does it stay or hit the floor? if it hits the floor there is air in your system or your prop valve is screwy.

 

This statement made by Clu7ch describes to a T the reaction of the engine running on the brake pedal! Sounds like I need to buy a new booster. Thanks everyone for your help I'll update the thread when I get a chance to change it out and report the outcome.

 

yep. thats what im trying to explain. Your booster is bad.

 

well, that's why i'm NOT a mechanic! i argued with my ex forever and a day about her car and the brake system, but she had to listen to her ex cause he worked at a shop (NOT ase'd mind you and a bit of a con shop) and NO ONE there thought to check the booster.