So the saga went on after running out if gas twice followed by a calibration & a software upgrade; ran out of gas again, this time on a freeway with more than 1/4 tank on the gauge with 102 miles on the range! Took it in to the dealer again. They contacted Porsche, and the Porsche now has a bulletin on this issue that has not been released to the public yet. My dealer followed that bulletin instruction, and redid wiring on the sensor, and recalibrated. I just spent several hours driving and monitoring the fuel gauge, and for the first time I git it down to near-empty with range of 26 miles without running out of gas!!! I hope this finally resolved this very annoying issue!

 

Thanks for the update.... Do you happen to know if this bulletin / fix pertains to a specific build date range? I've got a 2014 C4S June '13 build. Haven't noticed any issues with fuel gauge but I also haven't tried to "test" the accuracy. In the past two months only hit the fuel warning once, and it didn't seem too far from the truth....

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2014 GT Silver C4S

 

Glad its resolved. I too have a 2013 C4S and have not been stranded by the fuel issue, or lack thereof, but due to the info on this board I don't let the gas go below 70-80 miles to empty due to lack of confidence. I suppose I could test it cause when I'm driving the car a lot I have to fill every other day to avoid going below my pre-selected range.

 

Thanks. I've got my 10K maintenance coming up and I'll definitely make sure this is on the list. Hopefully they'll have the details by then.

 

It doesn't look like every C4S is affected. My dealer hasn't seen it happen in other 4S's, although if you fill up your gas at around 1/2 empty, you will never encounter this issue. Mine was one of the earlier C4S that arrived in CA, so maybe the later ones came off the lot w/ correct wiring. My fuel gauge would be fairly accurate until about 1/4 remaining, and then it's as if it got stuck. Since I don't drive it every day, I don't keep track of how many miles I've driven, and just go by the fuel gauge range that says 65 miles remaining, and next thing I know, I'm out of gas.

 

I think it's worth testing it by driving and monitoring your fuel gauge and the range starting around 1/4 tank remaining, and make sure it keeps on going down on range as well as fuel gauge needle until at least around 25-30 miles range to be sure. If it doesn't, you got a problem. Mine would get stuck between 60-102 mile range.