Codes for OBD 11

I have 2 codes I’d like to know what them mean to fix. P0017 and P00171

P0017 is Camshaft/Crank shaft position sensor. Before you go replacing parts, check you VVT Solenoid on passenger side, make sure the screens are not torn or dirty, AFTER a fresh oil change. Cleaning it/replacing it has solved a lot of P0017 problems on our platform. P00171 is system too lean bank one. This one could be a tough one, as it could be multiple things. I chased this myself for 6 months. Before you spend money, make sure your intake bolts are tight, inspect the corregated hose for cracks or leaks from the MAF to the throttle body. My problem ended up being the curly hose that goes from plastic resonator on top (says Vortec on it) to the valve cover in front on top. Try putting a hose clamp on this, on the both sides. Was a $10 fix AFTER I spent money to have smoke test done. Smoke did not leak out of this, but leaked enough to set the code, and was loose. MAF, fuel pressure are other things to check.