Fuel pump

Jim Isaacs wrote:

What I find curious is that this never happened before changing the old pump.

Is this  old/new the mechanical/engine powered, always on pump, or the Boost pump?

Either way it is always possible that the new pump is not delivering the same performance as the old. Could be within specifications but near the lower end of performance. New does not always mean better or even the same. There can be and often is differences in factory assembly.