I read that it's output is a DC voltage level, and I've read that it's a resistance level between the signal wire and Chassis ground. Can anyone clarify which it is for me, and what the range is?

Thanks in advance

 

From the manual: The TPS is supplied 5 volts from the ECM (5v REF) and sends a signal back to the ECM (TP Sensor Signal) which varies according to the throttle position. The output signal from the TP Sensor varies from 0.40 - 0.60 volts at idle (closed throttle) to 4.6 - 4.9 volts at wide open throttle. A code 11 will set of the TP Sensor signal voltage does not fall within the acceptable range.

The TPS sensor is a potentiometer, providing a variable resistance depending on the position of the throttle valve (and hence throttle position sensor). Note the drawing from the manual and symbol for fixed resitor.

 

Thanks for that. I read every word in my FSM about the EFI and the TPS, but somehow missed that. And the pot nature of the mechanism explains why it's commonly tested with an ohm meter in spite of the relevant data being in volts.