Finally at my wits end. Replaced distributor cap, rotor, coil all with Accel parts. New Taylor wires, New plugs set at .040" checked all grounds, great compression, new injectors, new fuel system with adjustable pressure set at 45psi, SCT tuned but still getting P0300 random multiple misfires not always same cylinders. She seems to be running fine under most conditions except under heavy throttle and higher RPM'S. that's when a mild misfire is noticeable but that's not when it codes out. Can my cam sensos (fuel sync) be out just enough to be doing this but not setting a CPS code???