You have to make sure you drop to a colder pluc! Those wires run very hot! Watch your plugs regularly and don't strip them out. Make sure you have brown on the plug and absolutely NO WHITE! Idon't like those coil packs because they run your car very lean up past 35oo rpms. Here's what you should do...Take your car on the highway and run it through the gears, but keep your car in 3rd while maintaining 4-5k rpms. Do that for maybe 1/2 mile and find a spot to pull over, preferable off the exit. Turn your engine off and check one of your plugs with GLOVES on! Make sure it's light brown and not white. If you drive your car on the highway and you live more than 1 mile to your house, your plugs will already have richened back up again and you'll never no the diff.! Good Luck