How do you change the spark plugs on a 2004 Volvo S60?

Remove two black plastic covers from the top of the engine. You will need a star bit, size 27 or 30(sorry I can't remember which). The covers extend the width of the engine and you will have to remove the two front mounting screws from the air tube that restricts access to the covers and plugs. I have a turbo model, and this may only be on the turbo version. There are five spark modules directly under the cover you just removed. They each have wires leading to them and are held in place by one 10mm bolt. The spark modules have a long cone on the engine side and the very bottom of the cone plugs into the top of the spark plug. Your will need an extension for your spark plug socket as the plug is a couple of inches below the top of the engine. It's pretty easy and shouldn't take over half an hour if you have all the tools.