thank you very much for your help, i treid the old mc ,which worked perfect b4 the the car sat for four months),but the same conditions came back?, i do have a tiny bit of moisture and air coming out of where the mc is bolted on to the booster when the pedal is pumped??

could the booster be screwed, and how can i test it?? thanks

If you have leakage between the the booster and master cylinder, then yes, the master cylinder needs to be replaced. I am replacing mine also due to the pedal sinking to the floor and slight leakage.

the same conditions happen when i put back my old MC on ???that'* why im thinking it'* a leakage originating from the booster ,??
thanks

The booster isn't even part of the picture right now. You don't bleed with the car on and producing vacuum, so forget it. The fluid/moisture you see leaking from the booster is coming from the MC piston leaking, not from the booster itself. There is no moisture, fluid, or air in the booster. Only VACUUM, and that'* only if the car is running.

The only effect the booster can have is a HARD pedal if it fails. Think of it as bionics for your foot, nothing more.

You're either doing something wrong, or you have a bad replacement MC.

my old MC was in good working order , b4 the car sat , when i was getting nowhere with bleeding the system,the first time i re bleed the new MC again for the second time , no results , so i tried my old MC, still the same thing happened exactly, im thinking my next move will be bleeding all the lines at the abs controller ,if the booster doesn't need to be checked i can't think of anything else?