The gauges in ThunderPig have never worked all that well.. We've had trouble with the fuel and oil pressure gauges since day 1.. and recently we came to realize that the water temp is reading high as well.. I made a call to the company I bought the original gauges from and told them, I don't want to use their junk gauges any more and would like to find out what the size of each gauge was so I could order some new Auto Meter gauges..
The guy didn't even skip a beat and said, "Oh we've had a lot of customers contact us with gauge issues. The company we used to buy from went out of business.. Let me send you some new Auto Meter gauges."
I was pretty excited! Because they're not cheap! Now I just need to install'em!
Keep your fingers crossed for me in hopes that the issues I've been having are gauge related and not something else ;-)