Would a loose fuel cap cause code P0456?

How Did You find your code? & Whats the procedure?.

Sincerely
Fustrated 2004 durango owner.

I didn't get it. It's my neighbors truck. I had him go to Advance Auto and borrow their scanner. He left his gas cap loose a couple days ago and the check engine light came on.

Straight answer. Yes, the fuel cap will pull a P0456 code. It is showing that there is a leak in the EVAP system.Almost any vehicle from 1996, and up with the OBDII system will show a code with the fuel cap loose, or missing.
Mike

yeah P0456 is a small leak detected in the emmision system, no big deal, fuel cap could cause it, depending on the year of the durango, if it's a 4.7L also check around the purge solenoid and the rubber hose coming from the intake plenum, they have a tendancy to crack when they get a little older...i know, i fix them all day long !!lol...there is also a small "elbow" under the truck (about right under the drivers seat) at the leak detection pump tha is common to crack causing the code