hi all just had them changed and the guy who did it said that the plugs seemed to be burning unevenly on the heads. more ware and tear on some plugs than others. also there was petrol found in the plug socket. what could this mean? keeping in mind that my v8 has become sluggish and feels like its running on 4 cylinders. and im going to get my ignitors and coils checked in the next week or so. im not driving the car at the moment.