Hi all,

My brother has 2008 S350 with 213k km. It has a fuel smell inside and outside the cabine. We took it to multiple technician but they couldn't identify the exact issue that causes the fuel to smell. Any thoughts??

 

I'd first check the both fuel filter and fuel pump lines which are under the rear seats. I think you'd know right away once you remove the rear seat.

 

We will check.
One technician told us that there is something that regulates the air pressure inside the tank and that thing is malfunctioning and causing the pressure to increase and thus the smell will be pushed to outside. I don't feel that his conclusion is correct

 

I had this same issue and as stated above it was a leaking fuel filter. Removing the seats and examining it yourself is very easy.

 

Latest update, we found that the leak is from fuel pump cover.
Thanks for the replies.