This vehicle had a low power complaint. One test that I love using is looking at rear oxygen sensor voltage when dealing with fuel trim codes or low power complaints. During WOT vehicles will go into open loop and run full rich. When this happens your rear oxygen sensor should reflect this (On a 0-1 volt scale, below 450 millivolts is lean and above is rich. Typically anything below .7 or .6 I start questioning if I have a fuel delivery issue. If I see the vehicle go full rich at wide open throttle I know my fuel delivery is good on the volume side of the system. As you can see in the captures this vehicle during WOT drops full lean on the rear oxygen sensor. Although not shown. Fuel pressure was checked and at idle was in spec, driving around with the gauge pressure dropped considerably. Fuel pump current was also taken before and after install of new pump.