This issue was covered under an early AEM bypass valve issue with the NTFS.
If the valve was purchased from an autherized AEM retailer and you filled in the warranty card a special plastic snap ring was sent to you to prevent this from happening to the bypass valve causing the TB to get stuck open.

AEM sent me one right away a few years back, it's worked fine ever since, it was about a 3min install to fix the issue. All new bypass valves have been redesigned since.