My 2013 Vespa GTV 300 will not idle now that I've come back to Oklahoma from a high altitude (8000-11000 feet) in Colorado. It was running fine when I left, ran fine while I was there and as soon as I got home it will not idle. This same thing happened to me last year with the same scooter so I swapped out the throttle body from my 2010 300 super until I could fix the issue or order a new throttle body because I wanted to take it back to Colorado this year. I herd voltage regulator can sometimes be a problem with idle so I took it to the Vespa dealer in Tulsa before I left out this year to have the voltage regulator changed out to make sure that wasn't the problem. It didn't fix anything. And switching out the throttle bodies moved the problem to the other bike made me believe it was the throttle unit and low and behold, it did it again! The second I got home, It will not idle. Now I have 2 Vespas that won't idle. but now that this has happened again and only coming back to a low altitude makes me think there's something I'm missing. I would appreciate any thoughts or fixes.