Sweet good to know I will keep it how it is

sent from my F-350

 

It should still read higher than 200F. To me it sounds like something is wrong. It could be the thermocouple (probe) but it could also be in the electronics inside the gauge. Before you spend any money, give the Auto Meter techs a call, describe your problem and see what they think. They may say something like it's the gauge, and if that's the case you don't want to spend your money on a new thermocouple if that isn't the culprit.