DIY: Fuel line repair! No more cold weather fuel smells! (04-08 Fxt)

If your Subaru resides in a climate prone to sub freezing weather you may have experienced this issue. If not lets discuss what and why this happens. With time comes degradation and on the Subaru fuel system time and temperature will cause a leak. Freezing temps causes the factory rubber fuel lines to shrink which in turn leaks out on to the engine causing a terrible fuel smell. This, under the wrong circumstances could cause a fire.. if the fumes that seep into the the cabin can give you an awful headache and difficulty driving your vehicle.

Not the easiest thing to find these leaks visually. This line hides behind the A/c and isn’t the worst offender of the leaking lines, but it can be seen without taking the entire intake manifold off.

Not the easiest thing to find these leaks visually. This line hides behind the A/c and isn’t the worst offender of the leaking lines, but it can be seen without taking the entire intake manifold off.

Ninety five percentage of the Forester's factory fuel lines are hard metal lines. With the last five percentage being rubber line connections that run under the intake manifold, another on the outside of the intake manifold near the fuel pressure regulator and and behind the A/C compressor. The most likely and difficult culprit of the fuel smell/leak is the two rubber lines that run under the turbo inlet. Removal of the intake manifold is necessary and I will link it shortly when the diy is completed.

Hard lines! They cover most of the distance, the two rubber lines that often fail are removed in this photo.

Hard lines! They cover most of the distance, the two rubber lines that often fail are removed in this photo.

Let's get down to the tools needed. We will need a razor blade, a pair of pliers and a screwdriver. You will need additional hoses replacement. You can reuse the factory hose clamps or replace them as well. 5/16” fuel injection hose 5/16” hose clamps 10 pack linked on Amazon. A few other tools that can be of help. Hose remover pliers, Fuel line disconnect tools and Gates hose cutter tool .

Here are all the lines in a row and measured for length. A little over a foot of hose.

Here are all the lines in a row and measured for length. A little over a foot of hose.

5/16” fuel injection hose is easily found at any local parts store. This is what you will need to repair these lines.

5/16” fuel injection hose is easily found at any local parts store. This is what you will need to repair these lines.

Most of the images below will show the hard fuel lines off of the intake manifold. This is not necessary but for an easier viewing DIY and the ability to paint the intake manifold, I went ahead with this method. With that being said I have many images like the one below that will show you where the lines sit on the manifold.

This is most likely what you will be looking at. You can leave the hardlines installed on the manifold and easily repair them. You can also replace your turbo inlet or vice versa.

This is most likely what you will be looking at. You can leave the hardlines installed on the manifold and easily repair them. You can also replace your turbo inlet or vice versa.

We will start with the two lower hoses under the turbo inlet. These are the most common for leaking and what should be your first step. After locating these two hoses, then remove the clamps for the ends of the hoses. Now take your razor blade to the hose cut a slit on both sides of the hose, this will allow for easy removal of the hose. As you may have noticed, they have become hard and brittle. This is exactly the reason why they leak. The hose has become so brittle that the clamp no longer puts enough force upon it to keep the fuel from leaking out. So let’s get our new hoses cut, placed on the hardlines and tightened down.

These are the two lines that are most likely the source of your leaking. These leaked on my WRX and then my FXT.

These are the two lines that are most likely the source of your leaking. These leaked on my WRX and then my FXT.

Clamps removed and placed above the hoses.

Clamps removed and placed above the hoses.

Removing the clamps show just how tight they are on their. Yet, those cold weather temps will allow fuel to seep out.

Removing the clamps show just how tight they are on their. Yet, those cold weather temps will allow fuel to seep out.

With the fuel lines cut you may now set them next to your new lines and measure out new hoses. Using your razor blade or hose cutter, you can now chop them to length and begin to slide them on to the hard lines. Making sure that the clamps were installed on the rubber hoses before pushing them over the hard line. You can decide which way the clamps sit on the hard lines, making sure that they do not interfere with the turbo inlet. I tried to install them in such a way that they can be re tightened after the intake manifold is installed but this doesn’t work. I would recommend installing them in the best manner you can or following how the factory installed them.

Using the razor blade cut the hose to easily remove it. It has become so hard and brittle it is almost impossible to remove otherwise.

Using the razor blade cut the hose to easily remove it. It has become so hard and brittle it is almost impossible to remove otherwise.

Now that the hoses are on in the clamps have been tightened down I recommend to tighten the clamps as much as possible. If you are at a stopping point this is a good time, take an hour break and then return to tighten them down once again. Allowing for time in between tightening the clamps fully, will help the rubber except the clamping force. if you have the ability to leave them overnight and retighten them this would be a great practice, allows the rubber to expand and except a clamp.

New lines on and clamps being situated to start the tightened process.

New lines on and clamps being situated to start the tightened process.

All of them slightly tightened down, we will leave it there for awhile and come back to tighten hem again.

All of them slightly tightened down, we will leave it there for awhile and come back to tighten hem again.

Later on, tighten them on down a bit further. I continue to run them down until the screwdriver will no longer grip the screw head.

Later on, tighten them on down a bit further. I continue to run them down until the screwdriver will no longer grip the screw head.

You may now begin on either of the other lines. The line I completed next was that 1 located near the fuel pressure regulator. This line needs to be precisely cut in the length of the removed line. If not the bunched up hose could cause a fuel blockage. I haven't seen any documented failures of this hoses but I went ahead and replaced it. This is the easiest hose to reach when the intake manifold is installed. It could be left on and replaced at a later time without intake manifold removal. Tighten up the hose clamps and you are complete with a another line.

This is the hose you can see on the front passenger side of the head. It is the least likely to leak, in my reading to ever leak but why not do them all. You can also repair/replace this line without removing the manifold.

This is the hose you can see on the front passenger side of the head. It is the least likely to leak, in my reading to ever leak but why not do them all. You can also repair/replace this line without removing the manifold.

This line does have a slight curve to it. Make sure your replacement hose isn’t any longer than it.. if it is, it won’t want to make the bend. Which could hamper fuel flow.

This line does have a slight curve to it. Make sure your replacement hose isn’t any longer than it.. if it is, it won’t want to make the bend. Which could hamper fuel flow.

The last hose to go is the one that sits behind the A/c compressor. If you remove the A/c compressor you can easily replace the hose with the manifold on the car. But once again if you have it off, why not take the time replace it and forget about it. This hose started leaking shortly after I fixed the two hoses under the turbo inlet. Using your favorite technique to remove this hose, with prior taken measurements you can cut your last line. Sliding it over both sides of the hardlines you can install the clamps and finish your task.

Last hose! Lets get this thing done.

Last hose! Lets get this thing done.

If you decide to do this on the car. This is how easy it is, remove the A/c compressor and with that you have plenty of room to work. The hose has been removed from the hard lines in this image.

If you decide to do this on the car. This is how easy it is, remove the A/c compressor and with that you have plenty of room to work. The hose has been removed from the hard lines in this image.

New hose installed.

New hose installed.

At this time I would remind you to retighten every hose clamps once more for a final check before reinstalling it into the car. The time spent double checking these clamps is a worth while investment. If you have to remove the intake manifold you will think to yourself… why didn’t I recheck them!?! I had to redo this task twice because I was sold the wrong clamps by the parts store. Now matter how tight they were turned they still leaked.

Old hoses and new hoses side by side.

Old hoses and new hoses side by side.

Congratulations! You have repaired your leaky fuel lines. Hopefully they will stay in the hoses and not return to your interior of your car or your nostrils.



Amazon links:

5/16” fuel injection hose

5/16” hose clamps 10 pack

Hose remover pliers

Fuel line disconnect tools

Gates hose cutter tool

Ej25 intake manifold gasket
















Dan EngstromComment