Shifting hard and codes P0700, P0716 and P0717

Okay. So you checked them for a short to ground. That is correct then.

When did the voltage jump to 2.5V and back to 0? Were you operating the throttle? Maybe get a video of this and show what you are measuring so we can get on the same page. Sorry, electrical is the hardest thing to help when not being at the car with you.

The voltage jumping up and going back to 0 like that is due to the probe moving and it creating its own voltage. Once it settles down and goes to 0 that is your reading. So all of those appear normal because the sensor was not plugged in.

At this point we need to go back to the P2135 and use a scan tool. Does your tool read data or is it just a code reader?

We need monitor what the sensors are telling the PCM when everything is hooked up and the only real way to do this is to monitor the PCM data.

Here is the testing that we need to stick too.

FYI - when you ohm out a wire you want to be on the wire by itself and unhooked at both ends. You do not ohm out wiring that is connected to voltage because that won't show you anything. Basically you are testing the integrity of the wire only. You can "practice" this by taking a 12 inch piece of wire and touch your black lead to one end of the wire and the red lead of your meter to the other end and you should have less than.5 ohms. This is ohming out a wire.

Correct. Resistance readings are wire end to wire end. You were checking for shorts to ground. It is a good test but just not a resistance test. If you are checking for a short to ground that means your wire is touching ground when it should not. Basically only ground wires should be touching ground. If any others have resistance to ground then they are shorted.

As for testing the 5 volt reference you would do it just like you are however, that is not your issue. Your issue is that the throttle position sensors are not reading within spec. So that means we need to monitor it with a scan tool because they need to be plugged in.

I hate to tell people this but I think we need a shop to look at it because I don't have a way to tell you to properly test this from here. You have proven out the wiring so we need the scan tool to see what is out of whack.

Yes. We need to check the voltage when it is plugged in but we need to do that with a scan tool that is able to read the data from the PCM.

As for your wiring diagram that doesn't show a TPS in the PCM, that doesn't seem possible because the PCM would have no way of reading it which would prove the sensor pointless.

I am not sure what is happening with that so if you don't have a scan tool, our best option at this point may be to have someone look at it.

Yeah. I can't explain why it is not listed. I can only imagine they call it something different on that list.

The fact that it is throwing some U codes points to a wiring issue. Those are normally communication faults so it will be interesting to see what they come up with.

Thanks for the update.