Common Ford 7.3 diesel high pressure oil pump symptoms include hard starting, especially when the engine is warm, rough idle, loss of power, and poor throttle response. You may also notice oil leaks around HPOP lines or fittings, engine misfires, or difficulty maintaining proper injector pressure. These issues can affect fuel delivery and engine performance, so early diagnosis and repair are important to keep your 7.3 Powerstroke running smoothly and reliably.