Through the kind help of my friend a retired mechanic,and the assistance of forum members, I have replaced the worn out transmission of this Malibu 3.5 liter V6 with a good used one. Everything works except the shift is rough and clunks at times. The OBD2 reader shows code 0717....turbine input speed signal is missing. This should be an easy fix, but we cannot locate the sensor. Various searches online have not been helpful. I suspect we have something left unplugged, or a damaged wire..there is nothing obvious on inspection. Does anyone know what I can look for, and where?

Sadly, chances are it'* an internal problem.......doubt it'* wiring if the code wasn't there before.....unless somehow the harness was damaged during installation....

Could be several things.....the sensor.....or there could be a huge discrepancy between the input speed and output speed, which means the tranny could be slipping....need to road test while watching input and output speed.....big discrepancy could be slipping clutches....erratic data from the input sensor could be the sensor.......not really familiar with this tranny, just speaking in general terms since no one posted....

Unfortunately, with any used tranny, you sometimes "inherit" the problems of the "father"....

Problem with the transmission was 3 bent pins unnoticed on the used transmission connector when the plug was attached.when these were straightened, and the plug reinserted, all the engine codes went away, Nd transmission is working well.

Glad you have the transmission straightened out with a few connector pins !