Fuel Gauge Stops at 1/2 Tank on 2001 996C4

[spg356]

I am aware of the saddle bags fuel tank setup I have on my 2001 C4 and that the gauge should estimate remaining fuel after 1/2 tank. However, my gauge just stops at 1/2 tank and stays there. Since it never reads lower it is up to me to estimate on my own how much fuel is left which has led me to run out of gas twice now, so I want to do something about it. After much searching here I read about many different issues with these C4's and their fuel gauge woes, just not this one in particular.

 

Any ideas? Thanks in advance.

[judgejon]

What you describe sounds to me like a problem with the fuel level sensor.  Should be an easy change out.

As you can easily fill up the tank, this does not sound like the fuel filler valve issue.

Good luck.

[Loren]

[creekman]

I have the same problem, but my gauge stops at about 3/8 of a tank.  In my case I have an LS3 V8 so I've interrupted what ever metering device was there.  I've been told that

the sensor in the tank reads to the bottom of the middle tank, then the Porsche computer takes over and computes fuel left and miles to go.  So if my information is correct you have a mechanical read to the bottom of the center tank, then a computer read out for the remaining gas in the saddle tanks.

 

There must be a transducer to read fuel flow by the computer.  I tend to think you don't have a sensor problem, but a computer problem...  I'll be interested in what you come up with, it's a pain to have to be guessing how many miles to go.  In my case my mileage can fluctuate from 12 MPG to 24 MPG depending how spirited I drive the car.

[spg356]

Thanks for the replies. We will do the recalibration as Loren provided to see where that gets us. Once done I will report back.

[dporto]

I've had this problem since I bought my car - the previous owner had it as well, and he ran out of gas. ** My "fix" is to reset my trip Odometer each time I refill the tank. With a full tank, I now check my trip odometer on occasion and when I reach 200 miles I refill the tank. This leaves me a reserve of about 100 miles (roughly 5 gal.). While this isn't what I'd call an ideal situation, it has worked well for over two years now and I haven't run out of fuel - not even close...Last time I was at my local dealer I mentioned the fuel guage problem to the service manager, and asked if he could recalibrate my gauge - his response was "no that can't be done, we'd have to replace the fuel level sender unit"...That's why I don't take my car to the dealer...