Knock sensor locations?

Both are bolted to the sides of the engine block below the exhaust manifolds. The left side is under a heat shield, you jack the van up and get to it from underneath. Remove the tin shield, then the knock sensor is there. Replace it and reinstall the shield. The right side is a bit more difficult as it is behind the starter solenoid, as such you have to drop the starter down to get to it. Then it's the same as the other side. The bolts for each sensor get torqued to 18 ft lb. Could I ask what the issue is as these sensors rarely fail on this engine and they do not share wiring?

Thank you very much for the help.

You are welcome.