did you check your coilpacks? spark plugs? how much boost r u running? sounds obviously stock to me, so im guessing you should run your plugs gapped at 1.1 or 0.8 depening on what boost your running and the heat range... 5,6,7 like BCP6ES 1.1 or 0.8mm or something. check your coilpacks wiring loom as well and plugs..