Fuel dumping in front of left rear tire

[Hal900x]

Hey guys,

Before I go ahead and buy a new gas tank I want to confirm my diagnosis. '90 325I coupe. First time I filled up the tank all the way, I got fuel dumping onto the ground right in front of the driver's side rear tire. It was coming out at a decent rate, not pouring but not trickling either. I'd say a gallon or two later it stopped. Since then I just fill it about halfway. Any more than that and the smell of fuel is immediately obvious. When that happens it's not obvious where the smell is coming from, but I can smell it the most clearly when I open the driver's side door. The smell does not seem to be coming from the exact same spot as the spill.

I'm guessing this is from a rusted tank, but I want to make sure the location of the spill is consistent with that. It would suck to buy a new tank and find out this is a fuel line, rail, vent tube, etc. Is the symptom consistent with a rusted-out tank? Thanks.

[bmwstephen]

well the fuel filter is right aorund that area. might want to check its connection to the hoses

[AndrewBird]

Pull the rear seat and check the tank there. The in tank fuel pump is mounted there and has an o-ring that is notorious for leaking.

[vpilarrt]

Some models (I don't remember which) have a 2nd access panel under the rear seat bottom. Might want to check that first. There are fuel lines and the chacoal cannister vent lines running along the top of the tank on the driver's side. You're probably going to have to drop the tank to get a complete picture of whats leaking (if its not a fuel line that you can see from under the car).

[jlevie]

This car has the 63L tank and thus a level sensor in the left side of the tank. It's seal may have failed. The sensor is accessible from the cover on the left side under the rear seat.

[Scallywagon]

Some models (I don't remember which) have a 2nd access panel under the rear seat bottom. Might want to check that first. There are fuel lines and the chacoal cannister vent lines running along the top of the tank on the driver's side. You're probably going to have to drop the tank to get a complete picture of whats leaking (if its not a fuel line that you can see from under the car).

:up:

[cutsham]

Pull the rear seat and check the tank there. The in tank fuel pump is mounted there and has an o-ring that is notorious for leaking.

Does the o-ring look like this by any chance... Having the EXACT same problem. Lol it's enough fuel that I get the wtf look from other drivers.

[AndrewBird]

Yup, that's the one.