Hall Effect RPM sensor grounding

Hi guys,

When grounding a hall effect sensor is it better to ground it to the ecu sensor ground pin or to the battery negative?

I normally use the sensor ground, but I would refer to the ECU documentation to make sure that's what they suggest for your ECU.

Most ECU manufacturers recommend to ground frequency-based sensors to the chassis, or your star earth point. Wherever you ground your injectors is probably a good spot. You definitely don't want to use the sensor ground, as the high frequency is likely to be a source of noise on the rest of the sensors.

I'm new here, and trying to understand best way to ground my hall effect too, but I'm reading a lot of conflicting info.. doing my very first harness and I thought that injectors are grounded by the ecu itself? ie, they are fed 12V switched, but the trigger wire is the ground from the ecu.. so I don't understand Matt's post above.

I also found this post on a diff topic: