I don't mean to revive discussion, but this thread almost has the answer I'm looking for. I followed the link to Nippon Ceramics and am pretty sure it is the part number NCEV***V2S5. The data sheet has a similar looking sensor so I think the wildcards might affect the actual housing but not the internals. The wiring is listed as:
- N.C. (No connection? It's blank and not otherwise described
- VCC (+5V) (on mine it is green with brown stripe)
- GND (on mine it is blue with white stripe)
- Output (on mine is yellow with black stripe)