I found out that all my couple month old motorcraft platium plug ( $3.99 a peice ) out fould from coolant because crack NPI intake, I swap in autolite 764 and car run like champ now
. I bet copper burn better in cold weather. dont use platium in your car
.
when i went to buy plugs last and i asked for copper plugs the guy behind the counter started to argue with me saying the car was "designed" to run on platinum. i said i know this, and id still like the copper. i dont mind changing them more often.