Yeah, to ground... the TPS signal line it VTA, not Vs... I had already moved ahead in my head with the other big possibility:
With a N/A the problem is more likely to be a flat spot in the VAFM's Potentiometer. Test pin Vs there for consistent voltage while opening the vane.
Test both though, they are both wear components... no idea why everyone buys used ones, they do have a limited lifespan.
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