The 1800 air filter is on the o/s inner wing. Pull off the clip on cover, remove the cold air scoop and look round the air box until you locate a series of metal clips. Undo clips and top half of air box will split away revealing filter. Sometimes its easier to disconnect the big intake hose to the air flow meter.
How do I change the oil filter on an Audi A4 Diesel 2007
behind the glove box
Over by the air filter's box.
Fuel flter, air filter, spark plugs.
beetween the trhotle and air filter housing
4 clips, unclip all four and pull element out.
is your a4 diesel ?
Call an audi dealer...
Open the hood of your Audi. To the left side you'll see the engine intake filter. Just above that and behind is the cabin air filter. It's easier to see if you remove the engine intake filer.
audidiy.com
lubricate the back where the old shocks used to be and ask a Audi dealer for A4 shocks
How much does it cost for a new starter on a 2000 audi a4 1.8t not quattro?