How do I diagnose Codes P0171 and P0174 at same time?

Hello, when you have both engine "banks" showing lean, as with this two codes, it's almost always related to an air intake issue - such as a vacuum leak or intake manifold leak. Unmetered air is getting into the engine causing there to be never enough fuel. I'd find it extremely rare to consider fuel delivery an issue with this vehicle. One known failure is illustrated by a technical service bulletin from Toyota which shows that the intake air control valve number 2 could have a vacuum leak. There is a test procedure to see if this is the case - but this is one possible cause of concern. Hands on testing is needed to figure out what is going on. https://repairpal.com/auto-repair-near-me