Hi
It's the original Ford VR sensor.
And yes, the lean issue is under investigation, it's only the right bank that goes lean, and at idle do it clearlt show misfires on cylinder 1 (isolated by disabling the injectors one by one). I've just changed injectors, with the result that both lambda's are equal 2/3 of the time. But sometimes do the left bank go lean. I suspect either a defect coil, or the vvt valve not working correctly. So I've just ordered 6 new coils and cleaned and inspected the VVT valve, and it's in good working order.
What's worse is that I took some pictures inside cylinder 1 with my endoscope, and the piston is slightly damaged from knocking, the other 5 cylinders is fine. So i'm back to beleaving that one of the original injectors was falty (that just don't explain the trigger issue ??)
Anyway, I'll check the compression, and put in new coils together with the new injectors and see if things improve. And the it's back to the road for further mapping work.