My trucks thrown a couple codes P1000. PO174 and PO171. 1000 doesn't say what it is. Idk If that's even a code. And 171 and 174 is sys lean. Bank 1 and system lean bank 2. It used to Idle rough when it was cold and sat outside all night. Then ran fine after it warned up. But it doesn't do that anymore and it's been decently cold at night lately I'm outta ideas.

 

P1000 is nothing, it is a code saying that obd checks (readiness monitors) are not complete. The lean codes are most likely a vacuum leak somewhere, the pcv hose is very common and is on the back of the intake. Could also be partially plugged fuel filter or weak fuel pump, but those would cause off idle issues more so than idle where as a vacuum leak would be the opposite. Probably should just get rid of that piece of crap truck, I would help you out with that and just take it off ur hands, lol

 

Haha. Well we did just trade for a duramax At work that I like... Haha
But I've been told its O2 sensors. PVC elbow leaking. Or intake gaskets

 

check the pcv first, you can use carb clean or propane and while the truck is running spray it around the intake and the pcv and listen for the engine to change rpm's. its best to have a scann tool and monitor your o2's and stft's but it is possible to do it this way too. Or if its a big leak you can hear it when you open the hood, it will be hissing. Its a really common issue with the pcv elbow at the intake, intake gaskets are not as common but still plausible, though they would most likely cause one side or the other to run lean not normally both. o2 sensors are most likely not the issue, o2 sensors are probably the most common unnecessarily replaced parts on vehicles today! they are not a common failure and will normally trip an o2 code with the lean/rich codes and cause other symptoms, but it is possible i guess. good luck