Thought I share this one with you.
I brought the car in last month for a few things and the check engine light that was on.
The dealer did a gas tank pressure test to find out I had a small hole in the aluminum pipe going from the fuel filler hole to the tank. This hole was caused by a ground strap grounding the pipe to the chassi. With vibration, the strap was rubbing on the pipe eventually damaging it slightly. Apparently, from what the mechanic told me, it is not the first time he saw this problem on the 2001 and up. The pipe isnt really expensive but labor wise, I was told 6 hours because the gas tank had to be dropped...
I fixed the pipe myself by removing the large rubber piece surrounding the filler end. I had to go by feel to notice a very small indentation in the pipe with my fingernail. Sanded the area and covered it with epoxy.
The light came off after 1 week or so (the car has to perform a few successfull tests in order to turn off the engine light).
Might be a good idea for all you late V70 owner to do preventive fix by securing the ground straps before it grind the pipe to a hole.
regards,
JF