Seadart - a different type valve he has (P2) actually not a valve at all, it's the Idle Stepper Motor (ISM) type. No air flows through it, so cleaning not relevant.
Ransoman - a good high peaked sine wave is correct for the Lambda, fluctuating between rich and lean is correct - that is what it does. (somewhere on here I posted a screenshot of a good wave)
Keep in mind your ISM might report well, but actually not be doing what it needs to. It contains several sets of tiny carbon rotary variable resistor tracks with brass pickups, bad design in my view
I changed it for the second time and that was a permanent fix, never had run properly in the previous 2 years despite all the usual things done. Try and find someone with a known good ISM and do a swap to diagnose?
Good luck, keep trying!