i read about this trick where you take spark plug foulers (or something) and drill them and then put them in your test pipes along with the factory o2 sensors and it prevens a check engine light . i was wondering - how does this trick work (technical details) and is it reliable?

 

https://my350z.com/forum/mid-atlantic/192858-labree-test-pipes-2006-350z-advise-please.html