On the 98 it is in the wheel well under the wheel arch cover.So
would think yours in same place, you will have to depressurise
the system first,but only a matter of taking out two relays in boot
( trunk ) turning engine over for a while.Part No. 34.81440.
Lucky for you the air filters going to the head lights are under bonnet
(hood).I will have to move mine back there,as at moment they are in the