Steps to replace a knock Sensors?

I had to do this last summer. First I went to Advanced Auto. They
read the code for me. One of them was bad, but I went ahead and
replaced both. I purchased a manual for the steps, two knock sensors
and a gasket set. About 170 dollars total. You will also need a torq
wrench in inch pounds. Take your time, keep it clean. Make sure
you clean the manifold and engine head surfaces where the gasket
seats. Use a non metallic scraper, and if need be solvent to loosen
any old gasket material. I found that laying saturated rags on the
head surface and leaving them set a few hours helped the most.
You can also get the steps and torque specs from either Advance
auto or Auto Zone(then you don't need the manual).
Use patience when tightening the manifold bolts, you should
torque them in the sequence given(in the manual or online) and
you have to do it twice, first time at half torque, then the second at
full torque. If you over tighten you can crack the manifold.
Good luck
Art LeDoux, Stillman Valley Illinois

If there is more than one replace them both. the knock sensor is under the intake manifold