I have a 2006 Volvo S60 2.5t FWD. It had a bad fuel pump (high duty cycle at idle) and replaced it with Bosch pump (has plastic tank). This fixed the duty cycle code. But now I can’t put more than 13 gallons in (from empty) or else it will leak from under the car on the driver side (looks like it’s coming from the top of the tank). I also have large fuel leak code. I figured it was because I didn’t put the new o-rings correctly so I put new ones on but the problem is still there. I also have the high duty cycle again which is also throwing a code. Assuming the pump is the problem again but how would the pump go bad with less than 300 miles on it? Any suggestions are kindly appreciated.

 

Are you confident that the pump is where the leak is coming from? You can get the high duty code from a leak and now your pump has to work harder to maintain the correct pressure. I would investigate the leak further. Check the lines around the fuel tank, and even the filler neck.