Poor drivability, especially uphill when it won't accelerate

What is your question?

2002 Mercury Sable GS has 64K on odometer. Fuel injector #5 was replaced 12/2020 due to drivability problem. Repair shop said car had PCM code P1151. Fluid levels are OK. Voltage is 14.1–14.3 while engine is running. Alternator and starter and battery were replaced in the past year.

What makes this problem better or worse?

driving, especially uphill

How long has your 2002 Mercury Sable had this problem?

A couple weeks