Originally Posted by Kbimmer
When you have to do etests ? do they send you a letter or something ? I never done one
Depending on vehicle age. If a vehicle is new its something like every 5 years and as it gets older its every 2 years. After 20 years its basically free for all and up to police to pull you off if your significantly puffing.
Not 100% sure but it's something like this.