Fuel Gauge Accuracy

Audio, Navigation, Electronic Faults and Fixes
xep
Posts: 45
Joined: Fri Mar 16, 2018 8:13 am
Location: Berkshire

Fuel Gauge Accuracy

Post by xep » Fri Feb 08, 2019 11:19 am

Hi guys

Maybe I'm being over pedantic on this, but it bugs me and wondering if anyone else has this happening to them.

I recently filled my tank up and the gauge doesn't match the figures for: 1) what's left, and 2) how much I've driven so far.

So you can see on my trip so far (reset when filling up every time), I'd done 70 miles. And I'd have approximately 353 miles to empty.
1- ( 70 / ( 353+70 ) ) = 83%
However the fuel gauge is pretty much full.

This is a real first world problem! But I wanted to check it's not an issue with my car specifically.

Thanks.

fuel2.jpeg

fuel1.jpeg

XE R Sport 240 MY16 | Bluefire / Jet Blue | Black / Privacy / Cold Climate / Parking pack

Deleted User 732

Re: Fuel Gauge Accuracy

Post by Deleted User 732 » Fri Feb 08, 2019 12:11 pm

The left stalk on the steering wheel column has several press alternatives to give the info required.
http://www.ownerinfo.jaguar.com/documen ... c/G1678965
You have to press the end button and HOLD to clear all the old info.
The distance to empty will vary with driving conditions ie long staedy journey may show 600 miles with a full tank but short journeys may show 400 to empty as it calculates from the driving conditions of slower stop/ start motoring.

PaulC

Re: Fuel Gauge Accuracy

Post by PaulC » Fri Feb 08, 2019 5:58 pm

I'd always take the distance to empty with a few bags of salt.
My previous 2 180D's never reported more than 530 to empty, yet I could do ~600 miles and still be above the red. My current XE-S never says more than 389 to empty, but I generally get ~400 as it gets to the red (not tested how many miles it gets whilst in the red, yet).

On a related note, there was a software update for the older cars relating to the fuel guage - has your car had it? (Checking TOPIx will tell you)

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Repairman
Posts: 479
Joined: Thu Jul 13, 2017 8:06 pm
Location: Dorset

Re: Fuel Gauge Accuracy

Post by Repairman » Fri Feb 08, 2019 6:41 pm

I think that most of the figures are calculated, and will never be 100% accurate, for example auto mpg doesn't even start recording until you have driven for a distance, and even then what shows on display at end of journey doesn't match what the journey has recorded on the Incontrol App.
Journey's always show a higher mpg, it gets interesting when you select instantaneous display, which I did once and travelled 4 miles keeping it above 80mpg, and at end of journey auto mpg showed 53mpg, and then you go into the eco screen on ICT and that shows a different figure again :)

The old fashioned method of recording how much you top tank up with and mileage, is the best method.
2016 XF Portfolio in British Racing Green. previous 2016 XE R-Sport in Italian Racing Red

PaulC

Re: Fuel Gauge Accuracy

Post by PaulC » Fri Feb 08, 2019 9:01 pm

The best method is to forget about how many miles you're getting per gallon, just enjoy driving it and fill it up when it's nearly empty :mrgreen:

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PhilB
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Location: South Buckinghamshire

Re: Fuel Gauge Accuracy

Post by PhilB » Sat Feb 09, 2019 6:16 am

PaulC wrote:
Fri Feb 08, 2019 5:58 pm
On a related note, there was a software update for the older cars relating to the fuel guage - has your car had it? (Checking TOPIx will tell you)
That was the early 163 and 180 diesels.
Some had the wrong software which due to the different sized tanks would show only 3/4 full on the guage despite being full on the filler.
2019 Evoque P300 HSE - now gone awaiting the "Beast from the West" est end of 2021
2017 XE S 380, Carpathian grey.
2015 XE S 340, British Racing Green.

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Mike Rometer
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Location: N. Staffs

Re: Fuel Gauge Accuracy

Post by Mike Rometer » Mon Jul 15, 2019 3:05 pm

Has anyone 'tested' the lower end? I decided against filling the other day (mis)calculating I had enough to see me through the week. I probably will manage but it currently shows '38 miles to Empty'. That may well drop some more when I start it, though I'll still have enough to get to the filling station, and some, How low have other pushed it? My last X-Type I got down to 7 miles on a couple of occasions and found no problems. If 'Herself' is in the car with me, she does her nut and calls me for everything. :lol: I just tell her consumption is better without the weight of a full tank. ;)
Jag No 3. 2 Litre petrol Prestige 200. Italian Racing Red. 65 plate

My other vehicle is coal fired. 8-) (very lo-tech)

Deleted User 732

Re: Fuel Gauge Accuracy

Post by Deleted User 732 » Mon Jul 15, 2019 3:24 pm

With a change of plan today we went to the lakes and I got 62.9 mpg. That was a mix of Mway and A roads. At the start of the journey we had 495 miles to go in the tank. We covered 223 miles and we now have the car calculated 429 to go (to empty) using the relevant computer calculations. On filling up I put in 47 litres which showed around 8 litres left working on the 55 ltr tank and the fuel guage showed 1/4 full so there is a slight inaccuracy there as 1/4 is just over 13 ltres. I prefer not to go below 1/4 and usually fill the tank.

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Mike Rometer
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Re: Fuel Gauge Accuracy

Post by Mike Rometer » Mon Jul 15, 2019 3:29 pm

I would usually fill up (T.t.T.) if below a quarter as I pass the pumps, just this time I did more running round for middle G/son than I'd intended. One fill easily lasts me a month.

We always reckoned that most cars still had around a gallon in the tank when they read empty. Hopefully gauges are a little more accurate these days.
Jag No 3. 2 Litre petrol Prestige 200. Italian Racing Red. 65 plate

My other vehicle is coal fired. 8-) (very lo-tech)

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Mike Rometer
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Location: N. Staffs

Re: Fuel Gauge Accuracy

Post by Mike Rometer » Thu Jul 18, 2019 10:45 am

Mike Rometer wrote:
Mon Jul 15, 2019 3:05 pm
Has anyone 'tested' the lower end? I decided against filling the other day (mis)calculating I had enough to see me through the week. I probably will manage but it currently shows '38 miles to Empty'. That may well drop some more when I start it, though I'll still have enough to get to the filling station, and some, How low have other pushed it? My last X-Type I got down to 7 miles on a couple of occasions and found no problems. If 'Herself' is in the car with me, she does her nut and calls me for everything. :lol: I just tell her consumption is better without the weight of a full tank. ;)
Filled up this morning with 32 miles to empty showing, that's got to be at least 3/4 of a gallon left. It took 59.31 ltrs. to the second 'blow off', and then read 464 M.t.E. Consumption over the tankful was 38.2 m.p.g.

What size tank is it supposed to be? ;) ;) :lol:
Jag No 3. 2 Litre petrol Prestige 200. Italian Racing Red. 65 plate

My other vehicle is coal fired. 8-) (very lo-tech)

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