PO 442 code 2002 GMC Envoy, can't figure it out?

[LTZ C20]

No you don't, my uncle did this on accident, the explosion gave my mom a rash for 2 weeks on her face and arms.

[78BIG-TEN]

Some aftermarket fuel caps wont work.I see this a lot code ,probably the most common
 code set.The canister vent valve usually the culprit,they can also cause the tank hard to
 fill,the gas pump will keep shutting off.Gm has a bulletin out on this

[LTZ C20]

Some aftermarket fuel caps wont work.I see this a lot code ,probably the most common
 code set.The canister vent valve usually the culprit,they can also cause the tank hard to
 fill,the gas pump will keep shutting off.Gm has a bulletin out on this

This is coorrect.