|  1) remove a vacuum hose from the pump of control of level of depression | 
        
         
          | 2) move connecting draft towards the vacuum amplifier against the stop  | 
        
         
          | 3) close the end of a vacuum hose a finger | 
        
        
          | 4) connecting draft should not return to a starting position; if it comes back to a starting position, it means that the vacuum system is not tight | 
        
         
           
              5) check the following elements for tightness:    – vacuum final valves;    – check that vacuum final valves were correctly installed;    – vacuum amplifier;    – vacuum hoses  | 
        
         
          |  6) eliminate the found leaks |