RS2 fuel lines - fuel leak

[JonRS2]

Hello. My 1995 UK RHD RS2 fuel line(s) (certainly the high pressure fuel line) are leaking fuel about half-way along the length of the car where there is a securing bracket. Leaking when parked up and switched off. Leaking more when the fuel pump is engaged and the engine is running. Probably caused by corrosion from 29 years of driving with salt on the roads. The fuel lines in the engine bay look fine. The fuel lines at the rear of the car look fine. The fuel line is straight (not bent) where it is leaking. I daren't undo the securing bracket to see if the non-high pressure lines are leaking too in case they all fall apart.

The car still starts and runs (but the fuel is disappearing faster than usual). I live near Twickenham (paying £12.50 per day ULEZ for the pleasure of driving).

I have a few questions:

1. Which is the best option for replacing the straight part of the high pressure fuel line in terms of material (steel to keep the RS2 as original as possible or some newer material?; what should be used for the high pressure connections?)?

2. What are the inner and outer dimensions of the fuel lines?

3. Where are the best places to cut the fuel line(s) in order to connect the replacement section? I saw a connection near the back of the car for the high pressure fuel line but I did not see a connection for that same high pressure fuel line towards the front of the car (other than in the engine bay).

4. Where can I purchase the parts that I will need? Either off the shelf or manufactured for me?

5. Who is best placed to do the work? The mechanic who looks after my car has told me he can do the work if I supply all of the parts, but should I be taking my RS2 to a fuel line specialist for this instead? If so, to whom? I am not a mechanic and am incapable of doing the work myself.

6. The fuel line closest to the side of the car is the high pressure fuel line but what are the other two fuel lines? Are they both return fuel lines to the fuel tank or is one a breather line? Which is which?

7. Does the RS2 have fuel lines that are unique to the RS2 or are the RS2 fuel lines on other Audis too? Is so, which other Audis?

There are no doubt helpful posts on this topic elsewhere in this great forum but I did not find exactly what I was looking for when searching. I am sorry if I have missed an obvious post on this topic.

The MOT is due on 23 March so I don't have much time to sort this.

Any help will be gratefully received.

Many thanks,

Jon

[Tractor Dave]

Hi Jon
They are all failing about now. The rubber clips hold moisture and slowly cause rust. It's not a big job to replace and there is a guide here. You need 8mm cunifer pipe and 8mm wade brass compression straight joints. The third line is a breather. We normally cut as they drop down from the bulkhead under the heat shield and at the back near the fuel filter. Rs2 is identical to S2 Avant. I think I've done 5 now.

[Tractor Dave]

https://www.s2forum.com/forum/techni...es#post2141198

[JonRS2]

Thank you very much.

I think I must have thought the breather line was the high pressure line (the one with the right-angle thingy at the rear near the fuel pump and closest to the OS of the car).

Do you recall which of the other two lines is the high pressure line and which is the return line?

Is cunifer better than copper or copper-nickel or are the three equally good?

Is there a particular best place to get the 8mm cunifer and 8mm wade brass compression straight joints or do many good places sell them?

[Tractor Dave]

I think you mean fuel filter. The pump is in the tank. The line coming out of the filter is the high pressure feed line. Good time to change the filter as well if it's not been done recently. Cunifer is copper nickle. Copper best avoided as it goes hard with time and can crack. I use ebay sellers with good feedback.

[JonRS2]

Thank you - showing my lack of knowledge. Yes, I mean near the OSR of the car. Is the fuel filter easy to access? I am not sure the fuel filter has ever been changed if it is not a service item. 160,840 miles on the same fuel filter? Hopefully the fuel filter is not NLA. Do you know the fuel filter part number for a 1995 UK RHD RS2? I read cunifer is copper, nickel and iron, but if cunifer and copper-nickel are interchangeable or the same thing, that's great. Thank you very much

[Tractor Dave]

Fuel filter is a service item but because access is tricky on the Avant, it's often overlooked. I think Audi will still sell you an oe one but Mann are good and much cheaper.

[JonRS2]

Thank you - from searching online, it looks like the Mann WK 725 is the correct fuel filter for the RS2.

[Tractor Dave]

I've done a quick search and I think you need 441201511c
I would double check as I can't get into the parts schematics atm.
Tell you mechanic he needs to undo the tank strap and drop the tank slightly to get access. Best done when tank is nearly empty.


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[JonRS2]

Thank you. There isn't much of a tank strap left!

[Tractor Dave]

I made some new ones from aluminium strip. I think someone in Germany was making new ones in stainless.


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[JonRS2]

Hi Dave, This is just to say "Thank you very much". I have now purchased some Saville 8mm Cupro-Nickel pipes from e-Bay and some Wade 8mm Brass Compression Straight Couplings from a Motorhome website. Just FYI, Flowtech told me that Wade is no longer in business but that a suitable replacement is made by Aignet (the ones I purchased are Wade though). I think Flowtech still have plenty of Wade in stock for the time being. Just the fuel filter to source now. The bit I am still unsure about relates to where to cut the fuel lines at the back of the car. Where they are still straight to make it easier or following the instructions to replace the bend and breather "thingy". Is there any advantage to doing the joints at the front first or the joints at the back first? Cheers

[Tractor Dave]

Where you cut depends on how rusty the pipes are at the back. I normally start at the front. If you do one pipe at a time, you won t mix them up.

[JonRS2]

The "Wade 8mm Brass Compression Straight Couplings" arrived from the Motorhome website - they were sold as Wade but clearly were not. They are being returned today.

For a higher price I then purchased Wade 8mm Brass Compression Straight Couplings from Flowtech, which arrived this morning and are the genuine article.

I have taken a photo of the difference between the two couplings. It is hopefully attached to this message.

[JonRS2]

Fuel lines now sorted. It is great to not have fuel spraying everywhere - a huge improvement on mpg and no longer a fire risk. Unfortunately, the fuel filter could not be changed even with the fuel tank lowered slightly as the existing fuel filter fixings could not be undone.

On to the next four items on my list:
1. checking the alarm / immobiliser antenna is connected properly as the fob sometimes doesn't work;
2. sorting corrosion to the suspension, heat shields, straps, fixings etc underneath the car (much worse this year for some reason - is stronger salt being used on the roads?);
3. sorting the droopy original headlining;
4. sourcing the correct Bosch aero wiper blades for the front wiper arms (side pin fixings - the wiper arms were replaced by MRC in June 2008 but I have no idea which type of car they are from) and the correct rear VW Touran rear wiper blade. I have tried calling Bosch but, without knowing which type of car my wiper arms are from and/or the Bosch code for the correct Bosch aero wiper blades with side pin fixing, they couldn't help me. They suggested what I am looking for may have been discontinued???