2001 windstar po171/174 code

i still continue to get the above referenced codes. i've done the isolator bolt repair, installed a new upper half of the intake manifold, replaced maf sensor as well as the egr pressure feedback sensor as well as the iat sensor. engine still continues to have a rough idle and stall after 15 minutes. have disconnected and plugged brake booster vac line and rough idle continues. brake booster line seems to have a strong vacuum on it. release my thumb off line and engine stalls almost immediately. installed new fuel filter also. van has 145000 miles on it. will install new pcv valve but doubt this is cause. is thier any easy way to check to see if fuel pump is the problem? or might it be something else. all thoughts are greatly appreciated.

IAC valve?

Need to run a smoke test to find that leak..