P0330 Knock Sensor

I have a 2000 Avalon with the check engine light on because of code P0330, knock sensor malfunction. Short of the $700 the dealer wants to replace this sensor is there anything else I can try or look into.

I show 3 hrs labor and sensors are about 200$ each.
But it could be wiring or computer or a no. of things.
Has the dealer checked it out or just gave you a price?
For some good repair info on it The All data online DIY subcription may help. Check out the link to it below.
MT-2500

http://www.alldata.com/products/diy/index.html

Knock sensors don't usually go bad. Most common is a bad connection (loose or corroded) or a damaged wire from other car repair work. Check the wiring and connections.