[drewzero1]

Depending on how old the enthusiast vehicles are, they probably don't have an OBD-II port (or possibly any port at all). None of mine do, up to the mid 90s.

[kQq9oHeAz6wLLS]

My truck barely has an electrical system (6v, positive earth), let alone a computer.

[fragmede]

1996 is when OBD2 became mandatory for all cars manufactured in the United States