My gas gauge seems to be reading off. A couple weeks ago I went to the store with a little less than half a tank and came out and started up the car and it said I had 3/4 full. Later that week I went to get gas and it said I had a little over quarter tank left and 19.5 gallons went in. 2011 G37 awd sedan if I remember it had a 20 Gallon tank. Only ever put premium 93 octane in it. Do I need a new gauge?

 

Just caught this and I'd suggest getting a tech to take a closer look. It could be the sending unit in the gas tank has become defective. Not an easy DIY. Be sure to update this thread and let us know what the problem and fix was.

 

I haven't had the problem fixed yet. Still there. A guy at work said its probably the floater in the tank, shouldn't be the fuel pump because the car still accelerates fine with no issues. I saw the other thread about the AC module and figured I might try that before putting a bunch of money into a mechanic. Someone suggested disconnecting the battery for about 45 minutes and then trying it, I guess to kinda reset everything.

 

So a guy at work has scanner and he scanned it this morning and this is what is wrong.
Engine code p0462. The service engine soon light is on as well. I'll probably take it to goodyear next week.

 

I took it to goodyear and they didn't see anything wrong with the pump or the sensor. Still not reading right. I fill it up and it goes past the line. Must be sometimes else.

 

I had an older BMW with similar issues, dumped two cans of gas treatment on a fill-up ( I don't recall the brand) and issue solved. Can't promise this will work for you but is was a cheap fix for me. Good luck and let us know how you come out on this deal.

 

I'll try that. Couldn't hurt.

 

Mine would show past full after a fill and would run out of gas a bit under half. Replaced both sending units with no change. it was the AC module behind the stereo.

 

That's what I'm thinking it is.