Replaced starter, fuel filter, PCV valve, and also injector seals. Also took the time to clean out the intake manifold, and head intake port. Was able to remove a lot of gunk! Did a test run after, and I feel like I regained quite a bit of horsepower. I thought it was in my head, so I took the wife out for a spin and she also agrees it feels noticeably faster. Could be better airflow through the intake port, or more fuel because the injector seals were leaking a bit, or maybe the old fuel filter was restricting fuel flow? Hard to say but I am happy!