Don't know what happens with MCP6L91 op-amp (not in my database).
But here is the behavior with AD8591 (inrail to rail, in my database) (AC analysis).
When the non-inverting is not polarized at 1.65V, the output is at -60db. When "well" polarized, it is a "band-pass" as usual.
NB: Must be checked in TRANsient Analysis with sinusoidal input, for example.
In red, what happens when V8=0, as in your "setup".
I also added the behavior with the "sensor" used. AC Analysis.
No fundamental change.