The oil filter is under the engine cover, just behind the orange oil dipstick. You will most likely need to get a special tool to remove the cap. The oil filter is inside. It's not a twist on filter like most vehicles. The filter sits inside a housing under the black plastic cap.
remove fan assembly (allen head bolt is in the back in a hole) - Jay 2004 passat tdi
How do I remove the headlight unit on a V6 TDI Passat year 2000?
go to the servise house
check out your local tyre centre or yellow pages
Go to library and find Haynes manual for your car
what oil do I use for a 59 reg vw Passat 2.0 tdi
how do you get rid ov a air lock in the cooling system on a vw passat 1.9 tdi 2000
http://www.fishh2o.com/Misc/Misc/Passat%20Radiator.html
If a Passat 04 TDI's indicator lights are not working, check the fuse. A blown fuse can cause the lights to stop working.
the book says every 60,000 miles or four years whichever is the sooner.Rob
According to the owners manual, 2005 Passat TDI timing belt needs changing on the 100,000 mile service.
google search freds tdi page there is a lot of helpful info