Pretty much the same for all Subaru flat four engines that use the coil-on-plug design but STi owners feel free to chime in with additional steps, if there are any. Just verify the correct spark plug application for whatever model you own.

 

do i have to remove the airpump and everything to change my plugs? i have a 06 wrx. whats a good gap for stage 2?

 

This guide was perfect in helping me replace my spark plugs.

 

I have a question if I unplug the power cord battery then does it affect the chip code on the keyless ? because the key has a chip inside.