Hello!
I relined my fuel lines last winter 05/06. In summer 06 the engine started with the problems. I thought it was the fuel delivery system or air in the lines. I filled the tank (was very empty) and everything was fine. While a ride the problem started again. If you put the hammer down fast the engine didn`t follow. It`s like a carburated engine with too much air or too less fuel.
Now I relined the fuel pump again, because the line between tank and pump was very muxh longer than my original setup. During cold start I thought it was ok, but when engine was warm idling got rough. It`s like that the engine wants to run fine but something suddenly stop this and the engine must hardly follow. Between these two stages I think there are 300-400 rpm.
Please help and don`t have any ideas!
Could this be the optispark system which isn't the best.
spark plugs? (I installed new wires 4 years ago=> 7000 mile max)
leak in the fuel lines?

 

Sounds like there is a problem when your pcm switches over to closed loop (occurs once car is warmed up). I would double and triple check all of the wiring and sensors to make sure that they are hooked up and functioning properly.