I have a 2007 Pontiac Torrent. The DTC was a P0455. EVAP Large Leak. I have replaced the fuel cap and cleared the code because I know its a common fix for that DTC. I drove it a day or two and the code came back again and it was the same DTC. What could be the cause? Thanks!

Welcome to AF, this is under warranty for 3/36, anyway a large leak can be caused by anything in the evap vent system, the usual method is to test for the source using a smoke machine, any other way is guess work and expensive. BTW in the future post in the Torrent forum below.