[dday916]

Hello Everyone.


I have a problem with my 2006 330i. When I'm filling my tank, as soon as I fill over a 1/2 tank it just starts leaking out the passenger side under the gas tank. The side where the fuel pump is. (I attached an image)

I recently changed my fuel pressure regulator and my fuel pump. This started happening right after I did this. I changed my fuel pressure regulator due to slow start and smell of gas in the vehicle and also my fuel pump because I was already going in there.

The slow start and fuel smell were fixed after I replaced these parts, but now i cant fill my tank over 1/2 way. I went back in to make sure gaskets were on correctly and everything was done correctly, so I tried to fill it up again, and it still started leaking right when I got above a half tank.

Please help I don't know what I did wrong... I followed all the steps correctly as far as I'm aware.

[jsunma]

I take it that it wasn't leaking (like this) before you removed the hats on the right side (to change the fuel pump) and the left side (the pressure regulator to address the smell of fuel).

But now that you've removed and replaced both of those pieces, it's leaking bad enough that you get fuel running out the bottom of car?

Have you lifted the seat and actually inspected the hats on both sides when you're trying to fill the tank beyond 1/2 full? It really seems that the leak has got to be coming from there. Probably the right side (based on your picture and also that the right side fills up first before the fuel equalizes in the two sides of the tank. I'd bet that you don't have the hat secured properly or you have one of the 2 hoses that run out of that side improperly/incompletely connected.

[jadams161]

You should not reuse the gaskets when replacing the fuel pump. This is exactly what happens. Have you pulled the seat up to see if there is gas on top of the tank???

[dday916]

Originally Posted by jsunma

I take it that it wasn't leaking (like this) before you removed the hats on the right side (to change the fuel pump) and the left side (the pressure regulator to address the smell of fuel).

But now that you've removed and replaced both of those pieces, it's leaking bad enough that you get fuel running out the bottom of car?

Have you lifted the seat and actually inspected the hats on both sides when you're trying to fill the tank beyond 1/2 full? It really seems that the leak has got to be coming from there. Probably the right side (based on your picture and also that the right side fills up first before the fuel equalizes in the two sides of the tank. I'd bet that you don't have the hat secured properly or you have one of the 2 hoses that run out of that side improperly/incompletely connected.

I'm guessing the hat is the plastic top part under the metal ring that you need the tool to remove? So, before there would be gas on the hat of the fuel pressure regulator side. That leak was causing the gas smell.

Now after changing both parts, both sides are dry. But I double checked the hat was secured properly before tightening the metal ring on top.

As for the hoses, I put the the two hoses into the clips at the end of the hose where the only gap to fit them into the clips would be. Third hose with the button & connector is secured properly. I went in a second time after seeing the leak to make sure everything looked right.

Are you saying i should take seats off while filling up the tank? and see if i can see any leaks on the hat then? because there isn't any residue or anything they both look perfectly clean.

Originally Posted by jadams161

You should not reuse the gaskets when replacing the fuel pump. This is exactly what happens. Have you pulled the seat up to see if there is gas on top of the tank???

I didn't reuse the gaskets. The fuel pressure regulator came with two, so I put one on the fuel pressure regulator side, and one on the fuel pump side. The fuel pump also came with one so I still have an extra one and I got rid of the two old ones.

Thank you both for the help I really appreciate it.

[mainbearing]

If the top of the tank is dry and no fuel leak is visible from under the seat, then I would get a bore scope inspect all over the tank.

[jsunma]

I guess I'd go with what Mainbearing is saying. It seems highly unlikely that your tank would spring a leak simultaneous with your replacing the fuel regulator and the fuel pump...but if you've checked all of that work (and your last post said that you did), then it makes sense to now look for actual leaks in the tank itself.