Depends on the source impedance from the device supplying the CT signal, vs the load presented by whatever value of pot you choose. (and of course that can change as you turn the pot). Also we would need to know the source impedance of your 2V and 7V references. Essentially it as a kind of electrical tug-of-war and we need to know how strong everybody is.

Now I am a little confused since your first drawing showed the pot supplying the motor directly and now you say it only provides a signal to a controller.

I just read BillBobs post and if this signal you have is PWM (which I have every reason to believe he is right) then your plan will not work.

If you need to receive one PWM signal and then create another different one to replace it, that can be done, but you would need to design a circuit to do that which would be somewhat complicated...

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1998 C230 330,000 miles (currently dead of second failed EIS, yours will fail too, turning you into the dealer's personal human cash machine)
1988 F150 144,000 miles (leaks all the colors of the rainbow)
Previous stars: 1981 Brava 210,000 miles, 1978 128 150,000 miles, 1977 B200 Van 175,000 miles, 1972 Vega (great, if rusty, car), 1972 Celica, 1986.5 Supra