SPECIAL TOOL: That is actually the cheapest special tool I can think off. I bought a whole box (different sizes) of them on Aliexpress for A$4.40. It's called "7pcs Pipe Disconnect Fuel Line Disconnect". It's required to swap the S-Type fuel filter, the S-Type fuel lines in the engine bay and the same in the X308, the fuel lines connecting to the fuel rail. X-Type fuel rail as well and obviously those 2 pipes. You fiddle it in position and then turn it 45° so that it hold up all 4 clips at the s