kinda hard to have the pump running if the engine is not running...unless you jumper the connector to force it to run...and then, there is not much load on the pump so the drop should not be very much.
Assuming you were checking the correct wire, try putting the meter between that wire and the car body and read the voltage drop...just in case the grounding is the problem.
Car running or not, FP running or not, ign on or not = moot! Proper voltage should be within .1-.3 V--NOT 2.9 drop indicated,,, Either there is a connection problem--or, like has already been said, perhaps 9.5V measurement probed on wrong wire???