PO170 and PO174 System Too Lean '15 5.3 Sierra please help..

[Closer_2001]

Installed the 93 Octane Easy Tune in my 15 Sierra
Really like the subtle improvements in shifting and the boost of mid range TQ

Unfortunately at every key cycle I was getting PO174 and P0170

Did a quick scan and saw LTFT at 20%+

Reinstalled backup for now not wanting to go lean and cause an issue.

[06MonteSS]

the tune doesn't cause a lean issue like that, because part-throttle fueling is not changed at all in the tunes..

so, something is up with the truck causing it...

need to check out your air intake, exhaust, etc.. make sure everything is all TIGHT so no air leaks anywhere, etc...

[Closer_2001]

Yep, one of the clean side breather tubes appeared connected but was indeed loose. Thnx, bone head move on my part