Got a code that wont go away

[droppedHoe]

i have a P0171
no other code, the truck runs great and is getting better than usual gas mileage.
where should i start?

replace the air filter, clean or replace the maf...
maybe the throttle body

i have plenty of fuel pressure and the fuel filter has only been on the truck for 700 miles...

i was gonna sea foam this weekend

 

[Anthony]

http://www.obd-codes.com/p0171

Read up there for info

 

[07Denali]

Spray some brake cleaner in the MAF with it removed from the truck. Don't be shy with the stuff. Let it dry all the way, reinstall, and reste the DTC.