does a gfi outlet also need to bonded to a metal box if an egc is connected to the gfi.
Does the metal box need to be bonded regardless of what type device?
Yes look at 250.146
Mine was a rhetorical question.
Does that mean you know the answer?
250.148(A) would require the box to be bonded.
250.146(B) would allow the metal box to be the bond for the device.
but what is a self grounding gfi outlet is use as per 250.146 D
but what is a self grounding gfi outlet is use as per 250.146 D
Self grounding will have a tension piece where the mounting screw penatrates the yoke instead of an insulator. The insulator can be removed and perform the same function