Hi
New to site but have a turbo gauge that works intermittently
Any ideas
Please

Picked up mine 2 weeks ago and had exactly the same problem. After giving the dash a clean as well as the said turbo gauge I took it out for a spin and hey ho it fired up. If you google search your problem as I did you'll see it's a common problem. See my recent thread.
https://www.fiatforum.com/500/479127-abarth-turbo-boost-gauge.html