Interesting in that the wiring diagram that
@wildfiremaint posted shows the earth shared bewteen TPS and coolant temp sensor. It shows the earth as a dot in the diagram but it could be implemented in a number of ways, earth bolt, internal loom crimp, etc... If this earth joint is dodgie, then the TPS reference signal can swing wildly (since the earth can fluctuate between 0 and 5V dependant on maybe vibration or engine bay temps). This is especially frustrating to fault find if it is indeed an intermitant vibration/heat induced issue....
So again it could be some wiring issue is at play as multiple TPS's can't be all be inaccurate/poor quality/faulty... Coolant earth is common to the circuit...
Old school works best when backprobing the TPS sensor wire as using an analogue meter it becomes easier to detect voltage sweep issues as compared to using a digital meter.
You could also try and unplug the water temp sensor and see how that goes