Fuel Filter

[Singh]

Hey Chaps, good to see everyone on the new forum. I was just wandering has anyone ever changed the fuel filter on the A8 or have a guide on how to? My cars running fine just want to do it as everything on its working at the moment and i'm bored!

[david@a8parts]

Hi there

Changing the Fuel filter isnt too tricky, its located under the rear drivers side just in front of the rear wheel, covered by a plastic shield.
You will probably want to get the rear end of the car up a bit to make it easier and get it onto axle stands as you are going to need your head under the car.

The fuel system is under fairly high pressure so depending on how long the car has been stood and not driven depends on just how much fuel will come out when you remove the filter. Its best to do it after the car has been stood for a while, say overnight, as the pressure subsides a little, be warned it can really spray out! Get some rags ready before you start! If you are in a rush and cant wait overnight then you can always pull the fuse for the fuel pump with the engine running and wait for it to die, but even doing this still leaves some pressure in the system.

To gain access to the filter you will need to remove the plastic shield by undoing the 8mm bolts that hold it in place. Under this you will see the filter and its just a simple swap out proceedure.
I would suggest cracking the bolts slightly and then waiting for the flow of fuel to subside before removing them completely. The New filter will most likely come with new sealing washers so use these, and it should also have an arrow for flow direction so make sure you observe it.

Once fitted and you are happy that all bolts are tight, turn the ignition on until the fuel pump stops whirring, and then off and back on again a few times. This builds up the pressure again. Now make sure it isnt leaking around the filter anywhere. Once happy try and start the engine, if it wont start straight away do the ignition on and off thing a few more times as obviously the new filter needs to be filled with fuel before it will reach the engine.

With my cautious head on I would say check the filter for leaks again after you have driven the car for a short distance, but if you are happy then refit the plastic cover and job done

[Singh]

Thanks for that David, very helpfull. I'm going to do it tomorrow. Off to GSF to get the filter now...

I have also done this - and it does spray as mentioned! Couple of things:
The filter is also held by a securing bracket - best to undo that once you have cracked the fuel lines, otherwise you will remove the fuel lines, have fuel running out and have to contend with the bracket holding it on as the fuel runs down your arm
Point 2 - watch out for the little banjo washers falling out. Normally with the filter you will get new bolts and washers, or washers at the least - make sure you remove the old ones as they tend to stick on the filter after being compressed on there for a while.. or it will leak if you mistakingly double washer it!
Very good idea to have it up on ramps or raised, as although the filter is located near the edge of the car, the cover over it has bolts securing it way into the middle of the underside of the car! Best of luck!

[Singh]

Now done, the filter was £13.75 from GSF. I took some pics which along with David and Simons info should give people an idea of what to expect when changing the fuel filter.
The first pic shows the car on the ramps, I left it overnight but there was still quite a bit of fuel that dropped out, some of it into my eye!

The second picture shows the panel that you need to take off, there are six 8mm bolts that hold it in place.

Third picture shows the old filter in place, it had the Audi logo on it so I am assuming it was the original.

The fourth and fifth picture shows the new filter and the new filter installed. I did have to turn the ignition key a couple of times to get the fuel running through the new filter but had no problems after that, done about 30ish miles on my new filter.



Thanks for your help David, wouldn't have known where to begin without your help.

EDIT: Just noticed in the last picture the filter isn't connected from one side, obiously I took the picture before I did!

Nice shiny new ramps (still got the label on?) and looks like the car has scraped some grass!?

[Singh]

Had the ramps for a few months now, about the grass, see my other thread.

[Singh]

Could this qualify to be made into a sticky?

[Conan_the_Librarian]

It's already linked to from the repair sticky!

Just a suggestion.
Did you replace the fuel filter? It sounds like your filter is plugged as when the pump is up to pressure and no fuel is being used, it will kick off. After letting it sit a small amount of fuel passes through to be able to start and run then will die do to lack of fuel.
Good luck and i hope you get it running