Fuel Gauge and DTE Readings

[Erni902]

Evening guys, I don't particularly have an issue just something that bugs me. Basically when I have a full tank and I drive for hundreds of miles the gauge and the DTE reading both display as expected and correctly.

 

The problem arises when Im coming toward the end of a tank or long journey. When the DTE reading gets to about 70 miles it seems to drop very quickly indeed regardless of my driving style or the gradient on the roads etc. I can do just 10 miles and lose 30 miles of fuel. The other day I was be 15 miles away from home with 77 miles on the display but by the time I got home the DTE was sat at 32 miles. I hadnt changed my driving style and certainly hadnt driven in such a manner that would reduce my fuel by that much.

 

Skip to today and I fire the car up to go into the village only 3 miles away, when I set off DTE reads around 30 odd. When I get to the village, pick up what I need and drive the 3 miles back I then end up with 41 miles in the tank.

 

The gauge also reacts in a similar fashion showing 1 minute on the red line then the next at 1/4 tank. The petrol lights looks almost like a disco light the rate it turns on and off. (slight exxageration, the light doesnt flash it just comes on and off again in tune with the 2 displays).

 

As I say the gauges all behave perfectly fine with no fluctuation when above around 70 miles, anything below this and its erratic and I have no idea if I genuinely have the displayed miles left in the tank or not. Its not a huge drama as I always plan my journeys around Shell garages and I rarely let it drop low as she mostly does long journeys so gets the tank filled every 250 miles.

 

Has anyone else experienced this? Is this a known issue with the Zed and just something to live with or do I have a fuel sender on its way out? Any advice appreciated.

[davey_83]

I dont have the same issue as you, but 100% the fuel gauge and DTE read out takes into account how the vehicle is being driven at that very moment. Ive been out on track and the fuel light came on, pulled into the paddock turned it off. Few minutes later and on flat ground, the gauge went back up to 1/4 tank.

 

In previous cars with no mpg display id always reset the trip when putting a set amount of fuel in, so id always have a rough idea of how many miles ive got left in the tank. Maybe try that, then later when you get a good idea on how far combined driving style 10 litres gets you - the rest is east math *as a guide

Edited June 26, 2017 by davey_83

[JetSet]

When the Zed is low on fuel a lot depends on the gradient, that maybe due to the large petrol tank or the shape of it? I remember when I first got my Zed I noticed that I was a bit low on fuel, 20 miles remaining. Within a mile and going up a hill it had dropped to --- so, panicking, I went to a get some fuel. This happened a few times and on one occasion I had to pop home before I got fuel. On restarting the car the reading had gone back up to 20.

 

2 Things, the low fuel light should not flash and once you get --- DTE then it'll remain on that until you switch the engine off and back on again. FYI, I once drove about 30 miles after the reading reached --- (on a flat road), there is obviously a considerable amount of fuel in reserve.

 

Pete

[Erni902]

I dont have the same issue as you, but 100% the fuel gauge and DTE read out takes into account how the vehicle is being driven at that very moment. Ive been out on track and the fuel light came on, pulled into the paddock turned it off. Few minutes later and on flat ground, the gauge went back up to 1/4 tank.

 

In previous cars with no mpg display id always reset the trip when putting a set amount of fuel in, so id always have a rough idea of how many miles ive got left in the tank. Maybe try that, then later when you get a good idea on how far combined driving style 10 litres gets you - the rest is east math *as a guide

 

I agree but the odd thing is that it doesnt matter how the car is driven. Once below 70 miles if I thrash it, then it drops accordingly, however on the exact same journey and exact same road with exact same reading at exact same point of the journey if I drive like miss daisy (or more accurately get stuck behind her) the reading acts exactly the same. Just seems alot more erratic when below 70 odd miles. Anything above that and it behaves exactly as I would expect according to driving style.

 

Ill try to remember to give that a go, I used to do that too back in the day but kind of got out of the habit and I keep forgetting until I've been driving for an hour or so haha. Need to remember to take my remembering pills!

 

When the Zed is low on fuel a lot depends on the gradient, that maybe due to the large petrol tank or the shape of it? I remember when I first got my Zed I noticed that I was a bit low on fuel, 20 miles remaining. Within a mile and going up a hill it had dropped to --- so, panicking, I went to a get some fuel. This happened a few times and on one occasion I had to pop home before I got fuel. On restarting the car the reading had gone back up to 20.

 

2 Things, the low fuel light should not flash and once you get --- DTE then it'll remain on that until you switch the engine off and back on again. FYI, I once drove about 30 miles after the reading reached --- (on a flat road), there is obviously a considerable amount of fuel in reserve.

 

Pete

 

Cheers Pete, when I switch off and on again the reading stays at pretty much what it finished on but then where I park is pretty damn flat and the road into the village does have a slight hill but its nothing steep and not too long. Maybe the Zed's tank is just designed in such a way that its more sensitive to movement and gradients than other cars?!

 

Maybe I should've worded it differently the light doesnt actually flash, it simply comes on when the reading is low and goes off when the reading is higher but the fluctuation in readings I get makes the light come on a go off. So the mileage will drop and the light will come on then 1 or 2 minutes later the mileage goes back up and the light goes off. Its just I dont spend my time looking at the light so one minute Ill look down and its on the next it will be off.

 

I didnt know that about the ---DTE reading not changing until you switch off and on again, that's interesting. My Cayenne sits at 000DTE for a worryingly long time then all of a sudden jumps up to 15 miles.

[JetSet]

My experience is that once the fuel warning light comes on (while the car is running of course) it stays on until the ignition is switched off and on again. We've had 2 Zeds, a prefacelift, which I've had for 10 1/2 years and an HR, which we had for 7 years and both have been the same. The warning light comes on with about 40 estimated miles left, my wife's Zed used to come on with around 35.

 

Once the ---DTE comes on then a lot depends on the type of trip you go on. For example, if I go to Asda and park up with a --- then when I turn on it may show 7 miles left but if I come home from Asda it may drop to --- but can read 20 when I turn the ignition back on. Oh yes, Asda is a sea level, I'm at 350 feet so I have to go up a long 8% gradient to get home. I also should add that my fuel gauge is very steady, no erratic behaviour even when fuel is low. I know that there have been a few reported problems on here with the fuel gauge causing incorrect and erratic readings.

 

Pete

[glrnet]

Most likely this http://www.350z-uk.com/topic/54763-how-to-fix-the-inaccurate-fuel-gauge-pdf/