Knock Sensor (KS) Removal/Installation: Notes

WARNING: This page is about a different car, the 2018 Mazda 6. However, it is still accessible from the selected car via links, so may be relevant.

Disconnect the negative battery terminal. (See NEGATIVE BATTERY TERMINAL DISCONNECTION/CONNECTION .)
Remove the plug hole plate. (See PLUG HOLE PLATE REMOVAL/INSTALLATION .)
Remove the intake manifold. (See INTAKE-AIR SYSTEM REMOVAL/INSTALLATION .)
Disconnect the KS connector.
Remove the KS. (See KS INSTALLATION NOTE .)

Fig 1: Knock Sensor And Bolt With Torque Specification
Courtesy of MAZDA MOTORS CORP.
Install in the reverse order of removal.