have a 7 series Toyota that is not producing enough vacuum to start engine unless add a slight restriction to air intake and engine will start and produces 15 psi of vacuum will idling, has 140 compressions across all cylinders performed leak down test on all cylinders all passed runs normal once get engine started and functions properly looking for cause of no start unless restrict air intake on carburetor, all parts of fuel system are new and to include governor and throttle body