i have an hreg 1991 escort turbo i brought about a month ago (3rd one)and when i brought it .It already had abaileys twin piston dump valve on it fitted with a t piece nicely done the problem is its shut when not running as soon as i start the car the dump valve opens up so its constantely open so its not boosting properly the vacum is to strong and put my mates new baileys on and it does the same so i know the dump valve is not faulty whats the problem need help havent encountered this before plz help