Just got a used 2000 4X4 quad cab dak.. It has 46,000 miles on it and I am currently updating all of the maintenance that was not done to it with last owner. I changed out the plugs today (they were the original-with gaps ranging from .05-.06). All new plugs are appropriately gapped at .04. After I was finished the check engine light now comes on. The truck is running like a dream and I took everything back off and re-checked all connections and plugs. Is the check engine light just the computer resetting itself to the new plugs?