I have an SES light on my dash and scanner revealed it was code PO440 "Evap Emissions Device." Anyone know how to fix this? I cleared the code for now but know it will come back up. Thanks for the help!

 

Usually P0440 is a missing/bad/leaking/loose gas cap. Try that first.

 

lol, damn! Imagine the poor guy who pays a gm dealer $100 bucks to fix a loose gas cap!!!

 

It can be something else too, just posted the most common/easiest thing to check first.

 

Also, make sure you're not filling the car up while it's running! That can sometimes cause a P0440. Like 2001NBMZ28 said, check the gas cap (basically the seal around the fill tube) if that does not fix it, you will have to have it hooked up to a smoke machine to find the leak. I just had to replace the Vent Valve on an '02 this week because it was stuck open. It's located on top of the gas tank along with the charcoal canister.