I needed to refuel today and I decided to go ahead and put $20 worth of gas (5.9gallons).....when I finished refueling I get in my car and notice my fuel gauge exactly where it was when I had pulled in....28 miles to empty. The thing didn't move a single micron. I go back to the pump to make sure the pump was actually flowing gas and not just air but the pump was fine. After driving around for 8 miles the gauge still wasn't moving. I go to another station and top off the tank.....this time the gauge moved but only to the half tank mark. After driving for another 5 miles it's showing less than 3/4 full.

This has never happened to me before. Once I fill it up it usually registers it immediately. Is this a gauge problem?

 

That used to happen to me with my 996tt. I haven't experienced it yet with the 997tt.

 

common problem

had it n my 996TT
now i have the issue on my GT3 and a friends 997tt has the same problem.

porsche apparently well aware of the problem

 

its a common thing when u put in abit of fuel ... it happens to me sometimes .. but usually resolves when i fill it up full afterwards.

 

Sorry for bringing up such an old thread but the same exact thing happened today to my 08TT, put $20 on a chevron because I could not get with the gas I had to a shell station, and the gauge is stuck at the same place, went to another gas station to fill her up, and it only shows 3/4 of the tank.... Any advice? Could it be a bad sensor?

Thanks

 

Some thing to do the fuel tank having a hump in the middle & the sensor is only on one side of the hump, so you have to fill it up passed the hump for the gauge to read, usually about 8-10 gallons .Always happens to me when i run it low to put in MS109 & i have to put in 10 gall for it to show.Def a design flaw i would hope got fixed on the 997.2tt

 

Each and every P car i owned had this problem...when reserve light is lit,you need to fill at least 30-40lt of fuel to make it show correct level...This has happened to my 986,996,996TT and 997TT

 

Ok ok ok you got me this is my first Porsche

 

I just posted a thread asking about a related question. My tank registered 3 ticks above empty. I drove to the gas station and added another 2 gallons to get a proper mix of 91/109. As I was pulling out, the gauge didn't budge. Thought it odd, then 1/2 a mile later, the fuel gauge light went off. Huh?? Thought to myself, how could the light go off after just putting in 2 gallons? Guess the above posts answers that.

So, approximately how much fuel is left in the tank once the light turns on?

 

You'd get more accurate info if you fill it up when the light turns on. The you'd know how your car registers low fuel.

 

Yeah, I know it probably would, but I was just trying to avoid filling the tank again with pump.

 

I have same issue. If I put 6-7 gal in the gauge will register no matter how low the tank is.

 

While the manual says approximately 2.6 gal remaining, I think approximate is the key word. I don't think the gauge is linear, except maybe in a certain range. When I run my tank down past the warning light, it seems like I can go for a very long time. If you have 3 ticks above empty and then you add another 2 gal and then a 1/2 mile later your warning light comes on, that tells you that you have more than 2.6 gal in the tank. It's a guessing game. I think it is more like (up to) 4 gal, although I've never actually measured it by filling up.

 

Ran my car low yesterday 12 miles til empty, I was in a rush so stopped and only put in $20. Started driving again, No change in gauge or miles til empty warning. I though the gas pump was messed up ?? Stopped at another staion down the road , Left the key on and while gas was filling watched the gauge start to rise and get to where $40 should be. Kind of strange but good to know it happens. Prob wont let it get that low if I can help it.. Adjusting to tuned gas mileage vs stock,, Still made it to my Hot Date in Time LOL......................

 

There is no problem with any fuel sensors. The AWD in the C4/TTs puts the hog head right underneath the fuel cell up front. The fuel cell is a saddle shape in order to accommodate this piece. There is a fuel pickup on each side of the fuel cell saddle, but only one sensor. This explains why your gauge reads the same amount of fuel. If you don't put in enough to cross over to the other side then the sensor never picks up.