I have 2001 venture who keeps throwing code p0327 low voltage to sensor. I have changed the knock sensor and pigtail to sensor and keeps throwing code. Any help would be great.

 

You've done what I would have tried - suspect the sensor was faulty and change it out. Other than a hidden frayed wire or bad connection between the PCM/ECM, it's possible that the PCM/ECM itself is out of order. (but that is usually less likely the cause). To be sure that the sensor that you just changed isn't the culprit, you can test it like this:
ps. - Welcome!