the problem is intermitent, sometimes it just won't rev over 2500 or 3000 rpm with no load or will hardly accelerate at all under load. i can hear engine clatter at part throttle under load consistently though, sounds like the fan hitting the fan shroud, but i know it isn't. have new main pump, FPR, fuel pump relay, AMM, O2 sensor, plug wires, and plugs. old plugs were white and the new ones are too. the knock sensors are cracking apart. the dealer said it was the intake manifold gaskets, but they're full of it, i checked those myself. the problem is independent of engine temperature or ambient temperature, and if the problem occurs the car can be restarted a couple of times and it does fine (still makes that engine noise though), indicates something electrical to me. i made the test light and half the time it doesn't flash a fault code, but when it does it's usually a 4, sometimes it does a 6 or 1 though. before i changed the main pump it sputtered when it had the problem, but now it just acts like it hits a wall and won't rev anymore.

any input is greatly appreciated.