Codes P219C and P11EC?

P219C - Bank 1 Air/Fuel Ratio Imbalance: This code suggests that there is an imbalance in the air/fuel mixture in bank 1 of the engine.

So, I would check for vacuum leaks and try servicing the MAF sensor but if cleaning it does not work, I would replace it with a new unit. Use this guide when the engine is cold only:

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

and

https://www.2carpros.com/articles/mass-air-flow-service

Here is the location of the MAF sensor below.

There is no TSB for valve guides.

P11EC (or similar codes like P11E9, P11EA, P11EB): This code isn't a standard OBD-II code and might be specific to Lexus vehicles. The exact definition can vary, but in many cases, codes in this range are related to issues with the air intake system, turbocharger, or engine sensors. It might also relate to the Variable Valve Timing (VVT) system or other components that affect engine performance and emissions.

Check out the images (below). Please let us know what happens.