Noisy fuel lines.....
 

Hi all,


2007 STi Spec D.
This morning at traffic lights I could hear what I thought was knocking on tickover....I mean, I thought I was about to spin a bearing or throw a rod.
..it was that bad.
Anyway, was on my way to Len at Subaru 4 You in Newbury where he had a listen.


It had been getting worse over the course of a week looking back.


Couldn't believe it when he said "That's your fuel lines"
And sure enough, he was right. It's coming from one of the two fuel valves - feed rather than return - near where the fuel filter is on a classic, by the passenger side front turret.


Len lightly crimped the feed line before and then after the feed line valve and the pulsing knocking / tapping noise stopped....seemingly ok since driving home too. You could hear it louder in the car....transmitting through the bulkhead where the lines are then hard plastic.


Seriously thought I was in for a huge repair bill....or possibly something silly like an idle tensioner....but never a noisy fuel line!


Anyway, will keep an ear on it and replace if need be....be about £90 for the bit I think, easy to fit.


Anyone else had this?

They are fuel dampers and come complete with pipework and clips, the feed being different to the return.

Fuel damper assembly return part number 42086FE040
https://i1011.photobucket.com/albums...l%20Return.jpg

Yep, that's them, hopefully only need the feed.

My feeling exactly, sounded so bad....Turned out something so daft!

Update, sorted.
Bits arrived Wednesday, bit of a pig getting the line onto the hard feed by the bulkhead. The hard pipe moves around a lot, and not a lot of room to hold it from behind and get the new rubber line on.


Anyway, noise stopped, and car runs a lot smoother.


£70 all in, not cheap, but hey I'm happy

Great stuff.

Maybe not... But a hella lot more welcome than the ££££s for the bottom end rebuild, you thought it could've been.

Big mercies. ;)

Oh yes!

Hey,

I just thought I'd chip in as I've exactly the same problem, I took it to one place and they did a compression test and told me it looked like ringland failure, repair bill being around £3K. I took it to Richard Henry Motorsport, who did a compression test for me, told me all cylinders were bang on 120 and the noise was the fuel lines. I've dodged a massive bullet.

For those that come across this thread the part number for the fuel line damper on the feed is 42086FE030, marked here.

https://cimg0.ibsrv.net/gimg/www.sco...7139810f44.jpg

Spec D right here: thanks for the heads-up, amigos!

Wow, that was a close call. Good job you chose someone honest like I did!


Strange though, the dealer I got mine from had never heard of a fuel damper fail, he's been in the Subaru trade many years and was sceptical it would sort it, but it did luckily.


I think an easy diagnosis is what Len did, crimp the feed with long nose pliers - the noise should stop, and engine would almost die off from fuel starvation. A very quick and conclusive test.


Happy days 777 :)

While I am waiting for the part to arrive from Japan, this has lead me to think about the fuel filter. It is due to be replaced at 60,000 miles which I am not far off. These posts might be of interest to you.

https://www.iwsti.com/forums/2-5-liter-litre-factory-motor/128053-dirty-fuel-filter-causing-car-run-lean.html

https://www.iwsti.com/forums/diy-mod...placement.html

ICP can get them.
https://www.importcarparts.co.uk/parts
https://www.importcarparts.co.uk/parts

Thanks, I've sent them an enquiry.

I had the exact same thing after an engine rebuild on my hatchback, I took it back to the builder thinking the worse, he couldn't identify it but told me it wasn't the engine. Anyway at home I started listening and thought it was come from the fuel lines, I removed them then refitted them and it never happened again. :D