it is the fuel pump... you need a new one, not the auto zone one but either a motorcraft or the dealership one.

 

I've had the same problem with my '96 F150 4.9 with duel tanks, but the problem is when warm starting from the rear tank only. If I flip the tank switch to the front tank, it runs fine. Befor I realized it only had warm start problems on the rear tank, a shop replaced my distibutor, repaired a vacuum leak but a smoker revealed no more leaks. Then when we knew it was a rear tank related problem, they replaced the rear fuel pump, but it still sounds like it's starving for gas on a rear tank warm start???? Any suggestions?

 

Does anyone know the name of the vacuum tube in the intake manifold is called? Auto Zone can't find it but my power brake booster is plugged into it and fuel pressure regulator is plugged into it. Like to replace it but it's not called a tree vacuum at the store. Help!!

 

Same here, I have a 302 v8 and it does the same thing

 

have a ford 150 v8 showing code PO 172