Truck's Running Poorly

[Garrett Street]

Well the topic title says it all. My trucks been running really bad these past 2 days. It'll have trouble idling. It will be going fine it'll be idling at 500, then surge to 800 then back down over and over again. It doesn't help to turn the truck off either. It still does it no matter what. It's somewhat intermittent because it doesn't do it 100% of the time, just the majority of the time. It just started a couple days ago, right around the same time we got a foot of snow.

 

Here are the codes it was throwing according to AutoZone.

System too lean- P0174 and P0171.

P0449

P0453

 

Any help would be great. Thanks a lot guys.

[8.1HD/ALLISON]

The lean codes are probably caused by leaking intake gaskets. Check with some carb cleaner. Search leaking intake gaskets. Bunch of threads.

[Garrett Street]

I was hoping for an easier solution. Lol