Getting P0171 code. Have replaced upper emissions hoses, throttlebody, mass airflow sensor and resealed valve covers. Thinking I may need to replace intake gaskets but I wanted to ask this group 1st before I tear into the car. Do the diagnostics I have posted appear to support bad intake manifold gaskets or are there other possible causes for the readings so I’m getting on my short and long-term fuel trims?

 

You have a rich LTFT with lean Bk1 fault.

your engine has too much un-meteted air on one side only... failed PCV crankcase diaphragm ?

Unless you dont have vehicle history I would not rush to focus on intake seals. They dont become wildly defective.
Even leaky tank purge should not be huge.

Do you have a dmoke test machine ??

 

I’ve tested the injector seals with the engine idling by spraying a small amount of brake cleaner at the base of each injector on the passenger side of the engine. On three of the four injectors on the passenger side, the engine stumbles when I apply the brake cleaner. I believe that is the source of the unmetered air.

 

nicely done!
If you're not in a big rush get them professionally cleaned up and tested for leak through + patern while injectors are out for seals.