so, after getting nicely warmed and smoothly running, the dashboard temperature gauge suddenly drops and pegs on cold...4-5 minutes later it comes back up to normal...then drops again after another half hour or so of driving...then back up...the only consistency is that it's damp here in the pacific northwest...does not seem to effect anything except my nerves...i want to make sure the 6.0 doesn't get too hot, so not feeling i can trust the gauge....any ideas about why?