If you have misfire codes and have eliminated plugs,coils, or any other sensor that could cause a misfire, check your knock sensor. It is hard to see and get to on the 03 accords or j series in general.
So after checking wiring and all sensors that could possibly cause a misfire i thought maybe an intake gasket was leaking. As i was taking the intake off i found one more sensor with a single wire and it ended up being a knock sensor. After wiggling the wire i could see the top of the sensor moving from where the plastic broke around the top of the sensor. It wasn’t completely broke to where the connection inside the sensor was broke but just enough to where it was getting a bad reading and not throwing a knock sensor code. Maybe this will help someone with misfire/random misfire codes on a accord with a 3.0.