well i was going to lunch and i hard a clank noise i thought it was a rock but turns out it my o2 sensor fell out of my turbo elbow........ wasnt even plugged in was just to plug the hole.

so what do you guys use to plug that hole i need to cure that nasty leak my sr sounds ugly i got a redtop if sr from a 180sx if that helps any

 

I welded Mine shut.

Orrr

Find a bolt and stick it in there?

...

Just weld it shut.
It'll take a welder 5 minutes.