99 deville p0300
 

Have followed everybody's advice, with no solution. Compresion good, fresh oil and filter, fresh fuel filter, good fuel pressure, no vac*** leaks, new plugs and wires, FPR good, new battery and belt, new MAF, Cam and Crank Sensors, swapped injectors and coils/ICP with known good ones. Still get 2-4-6-8 misfires and P0300 on the second ignition cycle. Any Ideas?