1998 Lincoln Continental P0192 Fault: Diagnosis and Solutions

I've been experiencing the P0192 diagnostic code on my 1998 Lincoln Continental for several months. Initially, I suspected a faulty gas cap, which I replaced recently—yet the issue persists. The vehicle now exhibits rough acceleration, particularly in passing gears, and struggles to start reliably. I replaced the fuel filter, which significantly improved performance, but symptoms have gradually returned over time. I tested fuel pressure: 10 psi with the engine off and 20 psi when running. Although I replaced the fuel pressure sensor, there was no improvement. Possible causes include a failing fuel pump or throttle position sensor? Any insights from owners of similar models would be greatly appreciated.