Tried to clear them with OBD link but they didn't clear, or immediately came back. I've since driven 45 miles and they're still there

I removed the EGR valve thingy and cleaned it up with carb cleaner and sprayed it down into the exhaust passages. I inspected the valve connector and don't see any bent pins... I do have a simple volt meter but unsure which pins to test for what and when.

I replaced the O2 sensor entirely, no change
Where's the other end of the wires? The battery wires had some serious corrosion on them so it's totally possible theres more elsewhere.

Any tips appreciated.

 

These aren't EGR codes so I'd leave it alone

There are two O2 sensors so it could be the other one (I assume both have heaters?). Or something with the wiring on the one that you did replace.

(un)fortunately I don't have more experience dealing with either, but if nobody else has suggestions, try youtube or googlign for these codes, there are often very good diagnostic guides and explanations.

 

The O2 code was for bank 1 sensor 1, that's the top most one right?

And the only stuff I found online for the other code was referencing it could be caused by seized EGR 🤷

 

Your approach seems good to me so far. Maybe check the wiring harness to the sensor?

 

Just checked it, there's no power to the connector for the EVAP valve with key in accessory position. No clue how to trace that wire or where to look now 😭