Chevrolet Repair Questions? Ask a Mechanic for Answers ASAP
that code indicates a "large leak" in the evaporative emissions system. The most common cause is a bad or poorly seated gas cap. But in all honesty, it can be something else too, like a broken or disconnected hose on the emissions evaporation canister or in the hoses leading to it somewhere.
There is also a purge valve on the evap canister that can go bad and cause this code. Trace all hoses that connect to the evap canister and look for a bad connection.
Is there rust or other buildup on the gas cap? Does the seal look ok?
Your vehicle is too new to have serious rust issues, but sometimes the tank breather (vent) pipe can rust through and cause this.