Fuel Breather Hose
Fuel smell in passenger compartment! Get it FIXED
A strong smell of fuel in the cabin is common on Esprits and something new owners often comment on. It's also something to look out for if you're looking to purchase an Esprit. This can be due to rusted and leaking fuel tanks, which is a big job, which can require the engine to be removed. The first think to check if you smell fuel while driving is the fuel breather hose which is prone to degradation and failure. The hose runs from one tank to the other above the rear window (see the picture above). This hose equalises the pressure between the two tanks on the Esprit, so it doesn't actually carry fuel, just air and petrol fumes. If the hose becomes damaged the fumes escape into the area above the engine bay quarter trim panels and into the passenger compartment via the seatbelt apertures. The smell can get worse with the sunroof or windows open.
It is a simple and inexpensive job to replace the fuel breather hose which can be undertaken by even the least experienced DIY mechanic. This will stop you needing a gas mask to drive and give smokers the confidence to light up again in their beautiful cars! (p.s. smokers, please do not read the above)
This job isn't difficult and will take you about an hour.
You will need the following parts:
2.2 meters of 10mm bore, internally braided fuel hose (external diameter approx 17mm)
You will need the following tools:
Cross blade screwdriver
Medium and small flat blade screwdrivers
Stanley knife (to cut new hose to length)
2 x jubilee clips
Fitting the Hose
(1) The first thing to do is remove the engine bay quarter trims. On my S4 these are secured by six fastenings. The lower four were screws, the upper two bolts locating into spire nuts. The trim then lifts sideways and out.
(2) The breather hose is the yellow/brown tube running from a flange on the filler pipe, above the air intake and along the inside of the quarter panel. The air intake system should also be in top condition to receive the best gas mileage and overall performance.
(3) This seems to be the most common area of failure – my car had splits in the hose here on both sides..
(4) The hose runs along the top of the rear window hidden by carpet.
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1. Engine quarter trim. Remove the six cross head screws securing the quarter trim
3. Mine had splits on both sides just to the left of the air intake...
4. Remove the quarter trim from the other side. The offending hose has discoloured and is brittle.
(5) If your model is one of those fitted with PAS, you may need to unbolt the power steering reservoir before removing the passenger side quarter trim.
(6) I found the best way of getting the fuel hose out was to follow the path of the hose to the rear window and then gently pull down from one side. This detaches just enough carpet to pull the hose free. It seems that the hose along the top of the window is often in better condition, but mine had been glued in place.
(7) You will see a plastic elbow and a further short piece of hose connected to a flange on the metal fuel filler pipe. The clips can be levered off using a flat blade screw driver.
(8) Once the clips have been removed on both ends you can pull the hose away. The shorter pieces of hose looked in OK condition and I was tempted to leave them. I’m glad I didn’t though as they were worse than they looked. My breather hose had two gashes each a couple of inches.
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5. Passenger side. You may have to unbolt the power steering reservoir on this side.
6. I found I could ease back the carpet by gently pulling the hose down.
7. Clips. The plastic clips can be levered off using a screw driver.
8. Slpitz. 2” hole on one side, 3” on the other… no wonder there was a fuel smell!
(9) I bought some internally braided fuel hose as a replacement. This stuff should last for ages and is much better quality than that originally fitted. You will need 2.2 meters (about 7’2”). This has an internal bore of 10mm (3/8”) and an external diameter of 17mm. I’d bought too much, but it still cost under ten pounds.
(10) You can see the plastic 90 degree elbow with a short piece of hose which connects to the fuel filler pipe. I was going to replace this like-for-like, but the fuel hose is much stiffer that the original material and I decided that the elbows need not be refitted, but they do have a use...
(11) I cut the new hose to length using a Stanley knife and heated the ends in boiling water. I then fitted and removed the plastic elbows to stretch the hose a little since it is a narrower bore than the original. You don’t want water in your petrol though, so let ‘em dry and have a cup of tea…
(12) Then you can push the ends of the new hose on to the fuel filler pipe flanges, secure with jubilee clips and feed the new hose into the gulley.
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9. New fuel hose. I used 2.2 meters of 3/8” (10mm) internally braided fuel hose.
10. Elbows. I don’t think the elbows are needed with the thicker fuel hose.
11. New hose
12. Refitting. The new hose just tucks back into the channel. Feed it back in, put the carpet back in place and refit quarter trim!
You may find that you need to stick the hose in place and / or stick the carpet back down but I didn’t actually need to do either.
This is a very common problem on older Esprits. LEW has heard many times of owners complaining of a fuel smell in the cockpit. Unfortunately is can sometimes be the fuel tanks, which then requires lots of labour and funds to fix. This is your first route to curing any fumes from reaching the cockpit. The fix looks easy and should give you years of fume free driving. Hopefully this guide will be read the performed by many Esprit owners.
Later Esprit vehicles had a moulded plastic breather hose to meet the new USA emission requirements. All the V8 fuel pipes had to be upgraded to meet the USA requirements. This resulted in a massive cost increase for the fuel system.
This mod was performed by Ian Russell on his 1988 Esprit, and can be seen at www.cytherean.co.uk
If you have any comments, feel free to e-mail us at firstname.lastname@example.org
There of course can be another reason for the fuel smell which an owener experienced even after they had replaced the breather pipe and checked the fuel tanks and that is if the charcoal canister is not working correctly. The canister is there to purge the fuel vapours at low and high revs and if the sensor is not working correctly or the connections are not good (as in his case) then the ECM will not tell the canister to purge the vapour and you get a fuel smell in the cabin..