The TPS is basically a potentiometer or variable resistor. It has three wires, red, pink/white and black/brown. The red also connects to the TOS, APS, STPS, IAPS and ECM using crimp connectors in the harness. The P/W goes directly to the ECM. The B/Br connects to the ECTS, STPS, IATS, IAPS and ECM using crimp connectors in the harness. If any of the crimp connectors has a marginal connection, the ECM will get the wrong info from the sensors.
I think what I would do in your situation is to check the ECM connector since that was not done yet. If it is alright, check the resistance between the TPS and ECM connectors of the same color. If the resistance is not basically zero red to red and B/Br to B/Br. I would add a jumper to bypass a marginal connection rather than hunt for a bad crimp connector. P/W to P/W is direct and shouldn't be a problem but checking it should give a value the other two should meet.