[Psyphertext]

After the last two fuel top offs, adding about 10 gallons at each, I have noticed an odor of fuel inside the cabin of my 2009 328i LCI. The odor is clearly stronger than the usual by-the-pump odor one would expect.

No fuel leaks showing under the vehicle.
No fuel leaks showing on trunk carpet or walls that I can see easily.
No fuel leaks showing by the rear passenger side seat of the cabin.
No odor prior to the last 2 fuelings.
Odor takes several minutes to clear the car with windows vented to circulate outside air into and through the car.


My concern is that this is on the same side as the battery and fumes venting into the car are obviously flammable. With certain prts of the battery connection being as fragile as we have seen, this has me concerned that I could have a post-fueling startup in-car ignition situation building.

Any ideas what this might be?

[HawkeyeGeoff]

Originally Posted by Psyphertext

After the last two fuel top offs, adding about 10 gallons at each, I have noticed an odor of fuel inside the cabin of my 2009 328i LCI. The odor is clearly stronger than the usual by-the-pump odor one would expect.

No fuel leaks showing under the vehicle.
No fuel leaks showing on trunk carpet or walls that I can see easily.
No fuel leaks showing by the rear passenger side seat of the cabin.
No odor prior to the last 2 fuelings.
Odor takes several minutes to clear the car with windows vented to circulate outside air into and through the car.


My concern is that this is on the same side as the battery and fumes venting into the car are obviously flammable. With certain prts of the battery connection being as fragile as we have seen, this has me concerned that I could have a post-fueling startup in-car ignition situation building.

Any ideas what this might be?

Check your LPFP. Take out your back seat and check. This isn't the first time I've heard of that developing a leak from the top.

[Thorin]

Check your fuel sending unit for cracks. Note that you want to do this with a full tank (weight of fuel can deform the tank enough to reveal the crack, but won't show when tank is empty).

[tlow98]

Why are you topping it off?

Does it make the smell if you follow normal fueling procedures?

[bluewater328]

Originally Posted by HawkeyeGeoff

Check your LPFP. Take out your back seat and check. This isn't the first time I've heard of that developing a leak from the top.

Have a possibly similar situation, but not sure if it just wasn't because I started the car in the garage and let it idle in the garage (of course with the garage door open). I think my smell is from the exterior (cats?)

Is there anything specific to look for as indicators? Imagine you pull the bottom seat and lift the rug?

[dugan42]

Originally Posted by bluewater328

Have a possibly similar situation, but not sure if it just wasn't because I started the car in the garage and let it idle in the garage (of course with the garage door open). I think my smell is from the exterior (cats?)

Is there anything specific to look for as indicators? Imagine you pull the bottom seat and lift the rug?

Pull out your back seat, take off the 5 or 6 nuts holding the inspection covers, don't need to unplug anything to look, but if you open those on either side and find any fuel, bingo.

Driver side = Fuel filter and pressure regulator assembly, passenger side is the fuel pump, they both have an O-Ring subjective to failures too.

Just did mine 2 months ago, soon as I lifted the inspection, there was gas, that area is now bone dry, both sides, dust around.