For years I bled air leaks from the fuel system by loosening injector nuts, or using the Schrader valve. Often it would take a few to several attempts to get the truck to start & run smoothly.I recently got the idea of using a Mitey Vac pump connected to the Schrader valve with an air chock to bleed the system. It worked great! It only took about 1/2-3/4 of a Mitey Vac jar & it was done. There was just a touch of stumble on the first start up & nothing since.