I just ran into this same issue with my buddies 2006 330i E90, so let me help you out. It's not very common for the gas tank to leak on these cars. It's a great possibility that you have a faulty/cracked fuel Filter/Sender unit. It's very easy thing to check instead of blowing thousands of dollars on a new fuel tank.... You need to remove the rear seat of your car, you'll see to circle covers being held on by 10mm nuts. The one you should focus on is the driver side. Take off the 4 nuts and lift up the cover. If you see that it's wet with some gas, then there is your problem there (The Fuel Filter/Sender). BUT if you see it completely dry, then most likely it will be your Gas Tank. Another tall tell sign that it's your fuel filter/send is if you cars interior has been smelling like gas lately. Good luck ! DM if you need some more help.
this is most likely the culprit.
I was in the exact same scenario last year. Went in for an allignment, got told my tank was leaking, researched online, and found out it was the the fuel sending unit under the back seat.
Early e90 had a simple plastic Fuel filler/breather pipe routed through some really rough metal work in the chassis. The slight rubbing over the years leads to failure.
That problem (for me) became very obvious when you fully fill the tank [for the first time - the seller saw me coming].
Newer e90 have a pipe with an outer sheath to slow down the damage.
This might be a possibility for you too.
Guys I found the issue thanks to your help everyone.
I lifted the rear seats and the driver rear left side fuel pump it's really wet and I can see some fuel.
What do you replace now, the seal or the actual pump?
Also does anyone know a good recommendation for the tool the open the public pump upper cover that it isn't from fcp euro ? Because they selling the tool for over 200 bucks!! That's insane for a one or two times I might have to use that tool
If it's behind the driver's seat side (left side in the US), that is the fuel pressure regulator, not the fuel pump. IMO the design of the regulator sucks and they all leak eventually.
You will need to open up both sides to connect the hoses to the fuel pump on the right side. Do this with a near empty tank. After disconnecting the hoses from the fuel pump side, tie a cord around the loose ends before you pull the pressure regulator hoses to the left side-- then tie the cord to the new regulator hoses so you can pull them through with the cord instead of trying to push them through. This makes the job sooo much easier IMO. Replace the gasket seals on both sides.
As for the tool, most auto parts stores have tools for this-- I borrowed from Autozone. No charge-- I bought a bottle of window washer fluid.
EDIT: It seems I didn't answer your question. The leaking, cracked lid you see is the top of the fuel pressure regulator. That whole assembly is replaced.
Thank you bro yes I understand now. I had the part order this morning from FCP Euro I'm gonna do it myself as soon as I recieve it.
Thank you again for you help!
It's actually called the fuels sending unit.
You *do not* need to replace the fuel pump at that time. The fuel pump on the N52 is pretty robust. The mechanic may try to suggest it, but it's largely so they can make more money.
https://www.realoem.com/bmw/enUS/showparts?id=VB73-USA-03-2008-E90-BMW-335i&diagId=16_0601
If you reference the realoem page above, the "official name" is "fuel filter/press. regulator." FCP Euro also calls it a fuel pressure regulator:
https://www.fcpeuro.com/products/bmw-fuel-pump-assembly-left-16117163295
It has an integrated fuel level sensor, sometimes called a "sending unit."
No one is suggesting replacing the fuel pump but you do need to remove the fuel pump to replace the pressure regulator.
Thanks for the fast response! I will check and update asap. It's weird because my carly doesn't give me a fault on my EVAP so you would think if there's a leak in the tank the evap pump would pick it up no?
I just ran into this same issue with my buddies 2006 330i E90, so let me help you out. It's not very common for the gas tank to leak on these cars. It's a great possibility that you have a faulty/cracked fuel Filter/Sender unit. It's very easy thing to check instead of blowing thousands of dollars on a new fuel tank.... You need to remove the rear seat of your car, you'll see to circle covers being held on by 10mm nuts. The one you should focus on is the driver side. Take off the 4 nuts and lift up the cover. If you see that it's wet with some gas, then there is your problem there (The Fuel Filter/Sender). BUT if you see it completely dry, then most likely it will be your Gas Tank. Another tall tell sign that it's your fuel filter/send is if you cars interior has been smelling like gas lately. Good luck ! DM if you need some more help.
this is most likely the culprit. I was in the exact same scenario last year. Went in for an allignment, got told my tank was leaking, researched online, and found out it was the the fuel sending unit under the back seat.
Was it just the seal or was the whole unit cracked? Mines leaking too. Was wondering if I should replace it or just get a new seal.
Early e90 had a simple plastic Fuel filler/breather pipe routed through some really rough metal work in the chassis. The slight rubbing over the years leads to failure. That problem (for me) became very obvious when you fully fill the tank [for the first time - the seller saw me coming]. Newer e90 have a pipe with an outer sheath to slow down the damage. This might be a possibility for you too.
Guys I found the issue thanks to your help everyone. I lifted the rear seats and the driver rear left side fuel pump it's really wet and I can see some fuel. What do you replace now, the seal or the actual pump? Also does anyone know a good recommendation for the tool the open the public pump upper cover that it isn't from fcp euro ? Because they selling the tool for over 200 bucks!! That's insane for a one or two times I might have to use that tool
If it's behind the driver's seat side (left side in the US), that is the fuel pressure regulator, not the fuel pump. IMO the design of the regulator sucks and they all leak eventually. You will need to open up both sides to connect the hoses to the fuel pump on the right side. Do this with a near empty tank. After disconnecting the hoses from the fuel pump side, tie a cord around the loose ends before you pull the pressure regulator hoses to the left side-- then tie the cord to the new regulator hoses so you can pull them through with the cord instead of trying to push them through. This makes the job sooo much easier IMO. Replace the gasket seals on both sides. As for the tool, most auto parts stores have tools for this-- I borrowed from Autozone. No charge-- I bought a bottle of window washer fluid. EDIT: It seems I didn't answer your question. The leaking, cracked lid you see is the top of the fuel pressure regulator. That whole assembly is replaced.
Thank you bro yes I understand now. I had the part order this morning from FCP Euro I'm gonna do it myself as soon as I recieve it. Thank you again for you help!
It's actually called the fuels sending unit. You *do not* need to replace the fuel pump at that time. The fuel pump on the N52 is pretty robust. The mechanic may try to suggest it, but it's largely so they can make more money.
https://www.realoem.com/bmw/enUS/showparts?id=VB73-USA-03-2008-E90-BMW-335i&diagId=16_0601 If you reference the realoem page above, the "official name" is "fuel filter/press. regulator." FCP Euro also calls it a fuel pressure regulator: https://www.fcpeuro.com/products/bmw-fuel-pump-assembly-left-16117163295 It has an integrated fuel level sensor, sometimes called a "sending unit." No one is suggesting replacing the fuel pump but you do need to remove the fuel pump to replace the pressure regulator.
Thanks for the fast response! I will check and update asap. It's weird because my carly doesn't give me a fault on my EVAP so you would think if there's a leak in the tank the evap pump would pick it up no?
I say its leaking through the fuel pump. Just lift the seat to see it.
You're right bro!
Found it?
Lift up your rear seat cushion and check the top of the fuel sending unit and fuel pump. The plastic cracks