Hey guys,

Picked up a new cabin air filter (which I swapped in 30 secs) and a new Bosch fuel filter from Audi yesterday. Just now I went to change the fuel filter but stopped due to the sun setting - I have read and searched for a 1000 posts/how to's on the C5 A6 and the proper way to change it - basically I think I have all of the steps down pat - but one thing I did not come across is what do you expect / is normal for when you first loosen the fuel line bolts from the filter?

As everyone mentioned, I took off the gas cap to depressurize the system and the car had been sitting for the past 5 hrs and is completely cooled down - however when I went to loosen both the IN (19mm) bolt and OUT (17mm) bolt (one side at a time) I had a constant stream of gas coming down. My question is - do you clamp the lines? Do they not need to be clamped and this stream is normal as it's really coming from the gas inside the old filter? Or is it / will it drain my tank if I continue to let it flow? This is the first time I'm changing a FF so I apologize for such an idiotic question - but I'll have to try and tackle this again tomorrow after work when I have sun light available - but any help is appreciated! I'm just not sure if the stream will stop - or should it only be a couple secs of stream? Mainly, I suppose - am I doing anything wrong? lol

Let me see if I got the steps right:

Unbolt clamp holding on filter --> Unbolt either 17mm or 19mm (one at a time) --> Remove old filter --> Prime new filter with gasoline --> Rebolt 17 & 19mm bolts to new filter --> Rehang new filter in clamp --> Crank car a couple times to get air out of the system / re-prime the system ----- Is that about right?? Thanks in advance!

 

Well I so far changed it twice. First time, I had fuel spill even after disconnecting the fuel pump fuse, and running the car until it died. It was just releasing residual pressure in line. Don't worry it will not empty your tank. It will just spill some fuel in the line and the filter itself.

Second time, I grew wiser and invested in a set of hose crimp pliers. Only leak was the fuel in the filter itself. So here is what I recommend.

1. Remove the fuel pump fuse. Start the car and run it until it dies. Mine died after about 3 seconds.
2. Remove the gas cap and re-tighten.
3. Get 2 hose crimps and use it on both sides.
4. Loosen lines with a catch can/bucket underneath it.
5. Replace the aluminum crush washers. Inlet and outlet are different sizes. You need 2 of each, total of 4.
6. You don't need to prime. Just install the filter.
7. Put the fuse back in. Turn the ignition to on position without starting the car for about 20 seconds. Try to start it. I will crank for a bit.
8. This is the important part! Turn the car off and check the connections. Make sure that you have no leaks!

Also you probably figured out, but you need a triple square bit to remove the filter bracket.

 

Thank you hx! That advice was EXACTLY what I was looking for! I had someone on AW respond and tell me about the washers! lmao Which didn't even answer my question - I already knew I needed 4 washers and got them at Audi when I picked up the filter It is raining in Pittsburgh today so looks like I'm going to have to wait, again, to do this!

Addendum: Where did you end up purchasing the hose crimps? The hose coming from the tank looks like it travels up to the tank and is in a tight spot - did you have any trouble accessing this line to crimp it?

 

I bought a set from Sears. I don't remember it being that tight, but I have an Avant so it maybe a bit different back there. Also as I said, the first time around I let the fuel spill to a bucket. It was less than a quart of fuel and high octane stuff always smell nice!

 

All the sets from Sears seemed to be like $50? There aren't cheaper ones around? lol or could I possibly use straight needle nose pliers or something else laying around the garage without damaging the lines?

 

Just get a bucket and let some fuel drip. No big deal.

 

I got the fuel filter changed today - car is running beautifully! - I just want to thank you hx for your help, brother! Couldn't have done it without your input and advice! Thank you.

 

Glad to be of assistance!