Hello,
When swap the connecting wire (Temp) going to the Oil or Temp it works on either one - correct? Depending on which sending unit I put it on that gauge works. It's the other wire (Oil) no matter which sending unit I put it on, neither work. I assume I have to run a knew wire from the Oil Sending Unit to inside the car.

Any other suggestions?

 

The oil and temp sensors work the same, the resistance value are different. Oil is a blue wire, green is for the temp.