Surging idle and some CEL codes, any likely causes?

2011 Prius

I have a P0101 for mass air flow sensor, P0441 for evap incorrect purge flow, and P0455 for big evap leak.

As well as a historic P0171 for lean bank 1, that popped up during that cold snap we had a few weeks ago, but it looks like it's not tripping right now, just is a historic code stored in the ECU.

First symptoms I experienced were about a month ago on a 1500 mile road trip. I work up, started the prius, got gas, and got on the highway. When I stopped for gas and a break about 250 miles later, the engine idle was surging up and down, both while in gear and driving and when stopped. I didn't have a CEL and didn't have tools so I didn't touch it until I got home.

I got home, took the intake box off and visually inspected the evap purge solenoid near the intake manifold. Hoses were cracked on the ends but they were on. I checked the codes and at the time I just had a pending P0441 an P0455. Not triggering a light, but they were present and pending. I cleared them to see what would happen.

That brings us to today. This morning I started the car, idle was surging so I shut it off, and when I started it again, I got the CEL and the codes I listed above.

Any likely culprits before I dive deep in? I have had the intake manifold off before and reused the gaskets. I have new gaskets coming in that I'm going to try putting on just in case.

 

So what my issue was, was the vapor purge solenoid (I think that's the name) mounted on the intake manifold. It would stick in the open position and the engine would just put a vacuum on the gas tank and was sucking in unmetered air and gas fumes.

I got a used oem one off ebay and put it in and the car has been running great for 6 or 7 months now.

This is an example of what I got, you can look around to see what is the cheapest/best one. I got one that had the mounting bracket and hoses on it too since mine were kind of cracked and in poor shape.

Toyota Duty Vacuum Switch Valve Vapor Purge Solenoid Sensor 90910-12279 VSV OEM | eBay

 

So what my issue was, was the vapor purge solenoid (I think that's the name) mounted on the intake manifold. It would stick in the open position and the engine would just put a vacuum on the gas tank and was sucking in unmetered air and gas fumes.

I got a used oem one off ebay and put it in and the car has been running great for 6 or 7 months now.

This is an example of what I got, you can look around to see what is the cheapest/best one. I got one that had the mounting bracket and hoses on it too since mine were kind of cracked and in poor shape.

Toyota Duty Vacuum Switch Valve Vapor Purge Solenoid Sensor 90910-12279 VSV OEM | eBay