First time posting here. I have a 2005, 4wd, automatic. The Service Engine Soon light came on and a quick check by a Nissan service center indicated a "code 4" which indicates that the issue is with the fuel level sensor. Does anyone have experience with this type of issue with the 05's? Could it be simply that I need a new gas cap? What else could be the problem? I plan to take the vehicle to be serviced in a few days, but I'd like to educate myself first so I can have an intelligent discussion with the Nissan service guys once I get there! Thanks.