Throttle Position Sensor test woth backward result?

[Kiwi944]

I am still searching for the stutter which comes in at 2800 rpm, which vanishes at full throttle.

The latest thing I have checked is the TPS. According to everything I have read, there should be zero resistance between DME terminal two and earth with closed throttle, infinite with it open. I am getting the exact opposite. Likewise, terminal three and earth should be infinite with closed throttle, zero on full throttle, and again I am getting the opposite result.

The car starts fine, idles perfectly, gets the splutters from 2800 on constant throttle but is perfect on full throttle. I am assuming that if the TPS is working backwards, the car shouldn't run properly at all? I am VERY confused...

Suggestions please?

Car is an 82-build 944