Fuel Gauge Reading Wrong

[dtroughton]

This may be common knowledge but it certainly caught me by surprise!

I was off to France where fuel is cheaper, on the way down to the ferry I realised that I was getting close to empty so I stopped to put in a couple of gallons to tide me over. When I got back in the car, the fuel gauge and miles to empty showed exactly the same.

Initially I panicked, thinking the gauge had failed or there must have been something wrong with the fuel pump I just used. However a quick Google on the iPhone revealed that due to the design of the tank and the position of the pick-up, when the amount of fuel drops below a certain threshold in the tank, the car estimates the amount of remaining fuel in the tank based on consumption. This is because it can no-longer measure it. If you do not put enough fuel in the car to allow the pick-up to register that the tank has been topped up, then the car continues obliviously and shows that you are running on fumes - most disconcerting!

When I got to France, I filled the tank and all was well - phew!

I thought this was interesting and worth sharing.

 

[richardjjs1]

Not quitter correct. You need to put 25 litres in the tank if it is low to show on the guage ITS A DESIGN FAULT Although Porsche will not admit it!!!

 

[Richard_Hamilton]

I think you'll find that it explains this in the driver's handbook. []

 

[dtroughton]

Thanks Richard I'm sure you're right, but I haven't seen it and I'm quite a nerd with such things (I'm really a bit sad). I guess Porsche figured that if you can afford one of their cars you can afford to fill up the tank every time[]

 

[Richard_Hamilton]

It has caught many people out in the past. There was one fellow on here some years ago who went back into the garage and demanded his money back! He managed to convince them, and drove away with about £20's worth of free fuel. He did own up to feeling guilty when he found out. Also covered here: http://www.porscheclubgbforum.com/tm.asp?m=346360

 

[thirteeneast]

LOL, Its a Porsche, Don't expect any of the gauges to be accurate [][][] Sorry[]

 

[spikey1]

Fuel gauge still empty after filling I found ones goes to 0 fuel gauge will register on sensor while driving then see fuel reading going up same if fill up leave the car on a flat surface over nite by the morning see fuel gauge giving a reading.

 

[philippe]

I have found this too but thanks to this Forum soon realised it to be an issue, I also find that when I fill mine up and it cuts out on the pump even if I add more which is always pretty minimal amount the gauge never reads 100% full even if it is, which is a little annoying.

phil

 

[Richard_Hamilton]

I have found this too but thanks to this Forum soon realised it to be an issue, I also find that when I fill mine up and it cuts out on the pump even if I add more which is always pretty minimal amount the gauge never reads 100% full even if it is, which is a little annoying.

phil

Maybe it needs re-calibrating, which is done with a Porsche tester. It is a bit of a faff, as you have to drain the tank, pour in a measured amount, and then calibrate the level sensor.

 

[richardabbott]

I too went back to a garage after filling up. Spoke to the AA man at the services. He couldn't find a leak. Having explained my predicament at the pumps we agreed to try and put more in. No more would go in!

Felt a little foolish. Thanks Porsche!

 

[9four4]

This catches new owners all the time. Almost every 996 we sell, the buyer is on the phone complaining their fuel gauge does not work..and then the disbelief that follows when they are told that's how they are from the factory.. I didn't know this was noted in the owners manual, I'll keep that under my hat..