Have 04 stock except for blow off valve and K&N Typhoon filter. Got check engine light, first couple of times it just flickered then when running a little hard came on and stayed on. took to autozone and they said a missfire on number 4. Put Super Conductor wires on it maybe 20k ago, car only has 124 k on it now. Replaced the plugs today with those E-3 things. took out and drove hard a couple of times, no light, didn't seem to run as strong as usual. Then when pulling up a slight hill in 3rd, have it a little gas and the light flickered on. Maybe the coil, have ordered a yellow performance coil (didn't say what brand) from Rock Auto. Will try it. I really don't think it is the wires. A couple of the Champion plugs had shorter electrodes than the other two. Any Ideas????