Every year when it gets cold outside my truck kicks error codes 171 and 174 for right and left banks lean. What do I do to fix this problem. I'm guessing either a tune or injectors. Any one know what to do? It is for a 2000 Silverado with 5.3, Custom cold air with the screen removed on the MAF, Hypertech, and straight exhaust with factory y pipe.

 

YEAR MAKE MODEL ENGINE SIZE MODS S/S# AGE GENDER.....GEEEZ were not mind readers...a little more info and maybe someone can help

 

Off the top of my head, I'd say that either the intake is warped and leaking, which could be affected more by the cold weather, or it could be false readings from the MAF which will also throw system lean codes. You could try cleaning or swapping the MAF (if you have a friend with the same truck and/or part number MAF), and spraying around the intake with carb cleaner while observing the idle to check for leaks. If that all checks out, I'd be checking fuel pressure, and viewing the vehicle data with a scan tool or tuning software...