Codes P0171 and P0174

This could be an air flow sensor but if you have both banks then you likely have a vacuum leak.

Here are a could guides that will help with this:

https://www.2carpros.com/articles/repair-lean-mixture-codes-p0171-or-p0174-on-some-manufacturers

https://www.2carpros.com/articles/how-to-use-an-engine-vacuum-gauge

If you don't find any vacuum leaks then we need to go through this testing to find out what the issue is. Please let us know what you find with this.

Below is the detail from the manual on the testing. Thanks

Good morning,

Just to add, one of the common reasons for these codes is low fuel pressure from a weak fuel pump.

https://www.2carpros.com/articles/how-to-check-fuel-system-pressure-and-regulator

https://www.2carpros.com/articles/how-to-replace-an-electric-fuel-pump

I attached the spec for you below. You can rent a tester at a parts store.

Measure with the Key On Engine Off with the fuel pump commanded "on".

Vin (V, T, U)
Fuel Pressure (gasoline) .................... 55-62 psi

Vin (Z)
Fuel Pressure (ethanol) .................... 48-54 psi

Roy