Gas tank is acting really dumb?
 

Okay so I drove my g35x 2004 till the gas light came on. I am well aware that the reserve is pretty hefty, something like 2 gallons if I'm correct? I went to the gas station to fill up and I only got 15 Gallons. Something has to be wrong I'm sure??? Since this car is advertised to be able to hold 20 Gallons. Could I have crap built up in the tank and that's why it won't really fill up to full with gas. Do you know how much it would cost to go to Infiniti and get it serviced for the fuel pump sensor and get the tank cleaned out I guess? I hear this is pretty common in the G35x

This car has a 16 gallon tank with a 4 gallon reserve. If your light had just come on you'll only get 15 gallons in. After your light is on awhile, the car switches to the reserve and the needle goes back to a quarter tank. There's nothing wrong with your car.

Oh damn I didn't even know that are you sure????? I'm not trying to drive my car into the ground and be stranded lol

Gas gauge acting up.
 

Okay so I drove my g35x 2004 till the gas light came on. I am well aware that the reserve is pretty hefty, something like 2 gallons if I'm correct? I went to the gas station to fill up and I only got 15 Gallons. Something has to be wrong I'm sure??? Since this car is advertised to be able to hold 20 Gallons. Could I have crap built up in the tank and that's why it won't really fill up to full with gas. Do you know how much it would cost to go to Infiniti and get it serviced for the fuel pump sensor and get the tank cleaned out I guess? I hear this is pretty common in the G35x. PS somebody told me that the tank reserve is 4 Gallons so when light comes on it'll stay there for a while then go back to a quarter tank... Is this true?

are you sure about needle going back to 1/4 tank lol?

I had the light stay on for awhile and I pumped in 17 gallons.

I am 110% sure. I've personally done it. Haha I guess it's not a full 1/4 tank tho, it goes up to that first big line from the bottom. So, yeah, that's probably right that 17 gallons would be accurate if yer light was on for awhile. You probably hit it right before the reserve kicked in.

The light turns on at 4 gallons remaining (approx). The needle is based on your driving habits. City driving the light will kick in earlier, and you may notice next time to turn on your car the light will be off for a fair bit of driving before it kicks in. Highway it will take sometime.
And the actual reserve portion of it kicks in at 2 gallons left. As for the needle going back up to 1/4, never knew about that tbh. I've always been too scared to take it down that low cause being stranded is one of my nightmares. So what you're experiencing is normal.

damn alright so Imma drive it till it goes to 1/4... Will the gas light come on again after it goes back up?