Excuse me for my spelling,but yeah I recently bought a 2004 350z Ent model with 50k+ miles on it and I've had it for about a month or so now. I've noticed a few things when I was broke due to the downpayments. In between those 2 weeks Ive been only putting about 5-20 dollars of gas.

A prime example will be if I put in 8 dollars of gas it will only give me about 1.80 gallons of gas due to 3.65 a gallon. And this is on a empty tank. After putting the gas in, it still stays on empty but when I start driving it will raise up after about 10 minutes and then drops again to empty then rises again. Im starting to think is due to the elevation and it varies from where I park. But one time I put in 20 dollars of gas and the i put my car on accessory mode. The gas needle did not move,but one I turn it off and turn it back on to accessory mode. The gas needle move all the way close to half a tank.

I've found this similar problem from a different forum

http://www.350zmotoring.com/forums/3...uctuation.html

and I guess the guy says you can complain to nissan about turning this into a recall,but how?? I've called before if theres any recalls on my vehicle and they said there are no outstanding campaigns or service recalls for my vehicle.

 

I've always been told (regardless of vehicle type) that you don't want to let your vehicle's gas tank stay below 1/4 tank of gas because the fuel pump needs enough gas in the tank so that it won't have to overwork itself. If there isn't adequate fuel, you can end up burning out your fuel pump.

I would suggest that until you can afford to keep more than the minimum 1/4 tank of gas always in the tank, park the car. Otherwise, you may end up with an expensive repair bill for a new fuel pump and installation, which will make it even harder to keep gas in your car, which will kill another pump... and the cycle goes on.

 

I have a 2004 350z with the same problem. I would fill the tank all the way but somehow the needle wouldn't be on full (it would mark about 3/4th or sometimes less but then eventually go up). I thought it was a gas tank problem at first, so I actually drove the car until my fuel ran out to make sure I was able to get 20 gallons in there and yup, sure enough, i was able to fill the tank with 19.7 gallons.

I believe there's actually a TSB for it. I just learned to live with it.
I'll fill up my tank to the max, reset the trip meter, and refuel around 300 miles or so to be on the safe side.

 

Wassup man? Just wodering if u fixed this problem yet?? I have the same problem i fill up every 200 miles lol