Just filled up with fuel, yet still empty? - Page 2 - Porsche General - PistonHeads UK

I had about 20 miles left of fuel in my 996 C4s earlier. Got £30 of super unleaded but when I drove off the fuel gauge hadn;t changed. Still said 20 miles and counted down to 15 miles when I got home. Switched engine off, left it and went back but still says no fuel.\ Maybe I filled up with air?! Any suggestions?

It generally happens when you refill with little fuel. I would have thought £30 (in a $50/bbl environment) would be enough to make the thirsty system recognise it but it appears not... Do not worry. Try and fill up with some more fuel and the system should adjust. Rebooting does not do the trick. 997s have the same "fault"

Normal on 4 wheel drive cars becasue the tank has two sides each side of the front diff. Level gauge only works properly when you fill right up! Mine's the same, perfectly normal and nothing to worry about. You're supposed to be rich enough to brim the tank when you own one of these, you pikey

Did you let it go really empty before refilling it? If so this can happen. You will probably find it is fine again when you next get in. I had it happen once - I put a full tank in, drove down the road then went back and complained that the pump wasn't working. Most embarrassing when I realised it was.

usually needs around 29 litres to register from empty

Ill go back and put some more in. Thought it might be something to do with not putting enough in. The manual makes out as if I only put a small amount in, but I thought £30 worth would be ok?! I don;t use the car daily so usually £30 would last me 2-4 weeks

oh and I was letting it go a bit further because this was the only garage in the area that I know of that does super unleaded. All of the others seem to do unleaded/diesel/superdiesel.

As has been said already very common on 4 wheel drive 996 model cars if you let the level get too low. Fill the car up and it will be fine and then function normally. Henry

Exactly the same thing happened to me. Lock the car and leave it overnight. Guarantee it will be working fine in the morning. Same thing happens to 2WD cars, it's a problem with the float in the tank from what I hear. Edited to add: Got a free tank of fuel out of Tesco's as "how on earth could a Porsche fuel gauge be faulty?" Felt like a monumental w@nker after that one!! lol Edited by Lagerlout on Monday 13th April 22:17

The Perodua Nippa has a fuel guage which works perfectly satisfactorily. In fact, I am pretty sure that most cars built in the last 30 years have a simple system that advises the driver how much fuel is on board. Its quite important information really. Porsche cant produce this basic function because the 4wd system gets in the way? When you consider Porsches innovations and engineering prowess over history, this is a little shocking. MTR

Just to echo what others have said- due to the shape of the petrol tank around the 4WD bits, the petrol gauge can only measure down to about 1/2 tank. After that, the on-board computer takes over and works out how much fuel/distance you have left based on your fuel economy. So the dashboard fuel gauge when counting down is pretty accurate, but unless you refill to more than half a tank full, it won't register on the petrol gauge in the tank. Has happened to me once, and others before me (see if the PH search function is any better, there were a few threads on this topic)

Maybe the same guy who designed the 996 engine is responsible for the fuel level gauge?

christer said: Maybe the same guy who designed the 996 engine is responsible for the fuel level gauge? I was going to suggest this, but didnt have your courage! MTR

mollytherocker said: christer said: Maybe the same guy who designed the 996 engine is responsible for the fuel level gauge? I was going to suggest this, but didnt have your courage boring predictability. MTR

Ray Luxury-Yacht said: mollytherocker said: christer said: Maybe the same guy who designed the 996 engine is responsible for the fuel level gauge? I was going to suggest this, but didnt have your courage boring predictability. MTR

big hair said: I had about 20 miles left of fuel in my 996 C4s earlier. Got £30 of super unleaded but when I drove off the fuel gauge hadn;t changed. Still said 20 miles and counted down to 15 miles when I got home. Switched engine off, left it and went back but still says no fuel.\ Maybe I filled up with air?! Any suggestions? This happened to me when I had my 996 C4S. I was unsure whether the pump could have delivered £65 of air rather than petrol. I returned to the petrol station and tried to fill up again to find the tank was actually full. Next day when I started the car all was back to normal and petrol gauge showed a full tank.

mine does something similar. go down to about 1/4 tank, fill it up and it doesnt register. leave it for a day and it then shows a full tank. lived with it for a year , but its going in for a service next week and have asked for it to be looked at. will keep you posted. dk.

big hair said: I had about 20 miles left of fuel in my 996 C4s earlier. Got £30 of super unleaded but when I drove off the fuel gauge hadn;t changed. Still said 20 miles and counted down to 15 miles when I got home. Switched engine off, left it and went back but still says no fuel.\ Maybe I filled up with air?! Any suggestions? I know I'm late to this discussion, but this just happened to me at a BP garage - filled my car up with £50 worth of diesel, paid for it - only to start my engine up to see my tank was still on the same number of miles before I 'filled up'. That amount should have filled my tank up adding to the 63 miles I already had when entering the garage, yet it didn't move the gauge at all. Cashier refused to help or believe me, telling me it was impossible and wouldn't even look at the pump in question to check. There is nothing wrong with my fuel gauge on my car - it worked all the way home counting down to the final fuel reserve warning which further proves the pump did not deliver any fuel!

yardbank said: I know I'm late to this discussion, but this just happened to me at a BP garage - filled my car up with £50 worth of diesel, paid for it - only to start my engine up to see my tank was still on the same number of miles before I 'filled up'. That amount should have filled my tank up adding to the 63 miles I already had when entering the garage, yet it didn't move the gauge at all. Cashier refused to help or believe me, telling me it was impossible and wouldn't even look at the pump in question to check. There is nothing wrong with my fuel gauge on my car - it worked all the way home counting down to the final fuel reserve warning which further proves the pump did not deliver any fuel! Just 12 years or so late. 😂

yardbank said: big hair said: I had about 20 miles left of fuel in my 996 C4s earlier. Got £30 of super unleaded but when I drove off the fuel gauge hadn;t changed. Still said 20 miles and counted down to 15 miles when I got home. Switched engine off, left it and went back but still says no fuel.\ Maybe I filled up with air?! Any suggestions? I know I'm late to this discussion, but this just happened to me at a BP garage - filled my car up with £50 worth of diesel, paid for it - only to start my engine up to see my tank was still on the same number of miles before I 'filled up'. That amount should have filled my tank up adding to the 63 miles I already had when entering the garage, yet it didn't move the gauge at all. Cashier refused to help or believe me, telling me it was impossible and wouldn't even look at the pump in question to check. There is nothing wrong with my fuel gauge on my car - it worked all the way home counting down to the final fuel reserve warning which further proves the pump did not deliver any fuel! You did resurrect a thread with a few characters I remember for both good and bad reasons!

pete.g said: You did resurrect a thread with a few characters I remember for both good and bad reasons! Mollytherocker is alive and well. Check the YouTube channel: Molly’s Garage.