johnss8 Posted January 15, 2007 Report Share Posted January 15, 2007 [ QUOTE ] My range normally shows about 250 Mind you I checked my MPG the other day and it said 14.5 [/ QUOTE ] Is that all mate you must be driving a little conservative again Link to comment Share on other sites More sharing options...
Jimbolian Posted January 16, 2007 Report Share Posted January 16, 2007 Well, full tank is about £70ish and i get around 300miles a tank. Which is every couple of days.. Still that's fairly spirited drive! : ) 4.2QS D2 1997 ( slightly dented still! ) Link to comment Share on other sites More sharing options...
AnArtist1 Posted January 17, 2007 Report Share Posted January 17, 2007 [ QUOTE ] full tank is about £70ish and i get around 300miles a tank. [/ QUOTE ] Same here, and thats with a lot of unavoidable short trips too. Link to comment Share on other sites More sharing options...
Jimbolian Posted January 19, 2007 Report Share Posted January 19, 2007 Well i normally get somewhere in the 200's out of a tank.. And have done a tank in just over an hour.. and most of the M1. But on a trip last night from Newcastle back home, my card got eaten so i only had £40 plus the scrappings of fuel in the car, queue a very legal very calm cruise home it did 267miles and was showing 10miles left when i got home and grabbed the spare card. But i'd rather blow the saved 20ish quid and spank past everything.. Link to comment Share on other sites More sharing options...
GlynH Posted January 19, 2007 Report Share Posted January 19, 2007 700 miles? Not in my S8... Costs 70-80 quid to fill her up with V-Power and the computer shows @400 miles to empty. If I drive carefully then I have seen it increase to 485 miles before it starts to go down but I am guessing in reality I probably get @350 or so to a tank. Average consumption is currently 23mpg which compares with my old 24v Scorpio... Strange thing is if I arrive home with say 70 miles to empty when I set off again in the morning the low fuel warning is on and it shows 40-50 miles to empty. Is one of you taking her for a spin while I'm asleep? Regards, -=Glyn=- Link to comment Share on other sites More sharing options...
ghemmings Posted January 19, 2007 Report Share Posted January 19, 2007 Glyn, it shows a lower value in the morning because your average mpg value is significantly less on a cold start due to extra fueling and slower speeds. The range is calculated using an average mpg over the last few miles of journey along with the fuel guage value of fuel left in the tank. When cold your average mpg is lower, so your range in the tank is shown lower, even though you have the same amount of fuel in there from the night before. Once warm and travelling normally, the range will have gone up slightly or remained at about the same reading a few miles later, because the computer calculates a new value with the higher average mpg value, and a slightly lower 'fuel remaining' value. Hope that makes sense!! Link to comment Share on other sites More sharing options...
sjmmarsh Posted January 19, 2007 Author Report Share Posted January 19, 2007 Glyn I have seen a similar thing once the low fuel light is on (80 miles to go). It drops to a range of 30 miles after 20 miles or so, but then sticks there for a while. A bit unnerving if you are a long way to the next fuel stop. Steve Link to comment Share on other sites More sharing options...
nikw Posted January 21, 2007 Report Share Posted January 21, 2007 In my experience it's not just the DIS that plays this game. I can arrive at work with 50-60 miles range left and the fuel gauge one mark above empty, but when I set off for home at the end of the day the gauge is then reading empty and I have maybe 10 miles range left. The range I can understand - as Hayne says it's calculated on recent MPG (last 30kms I seem to recall from somewhere) and becomes increasingly pessimistic once the remaining range drops below 100 miles. If the car hasn't been used in the last 2hrs it seems to use a fairly optimistic pre-determined figure (25+ MPG?). If you've ever looked at the instant MPG readout immmediately after a cold start you'll see that for the first half mile or so the fuel consumption is absolutely horrendous - I've seen 4-6 MPG while accelerating up to 20 MPH very gently, so of course the range figure will drop quickly to reflect that. The fuel gauge behaviour is more difficult to understand. I have two theories which might explain why the level appears to drop while the car is parked: (a) When the car is in motion fuel sloshes around in the tank. This means that the level displayed on the gauge must be an average of measurements taken over a period of time if it is to be accurate. With plenty of fuel in the tank the law of averages dictates that for every upward slosh there will be an equivalent downward slosh, so the gauge reading is a reasonably accurate measure of the static level. However, when the level in the tank is very low, maybe an inch of fuel covering the floor of it, the upward sloshes can still be big (say 3 inches) but the downward sloshes can't (max 1 inch to floor of tank). This would cause the average reading to be greater than the static level thereby making the gauge over-read while the car is in motion. Once the car has sat still for long enough (parked) the gauge will show a more accurate reading, one that is lower than when the car was in motion. (b) The same pessimism programmed into the DIS range calculation with the aim of protecting us from ourselves somehow also affects the fuel gauge. When fed a signal indicating, say, 10% remaining in the tank the gauge shows a lower reading when starting from zero (ignition off) than when it has dropped down from a higher reading during driving. This behaviour is intended to scare the driver into refuelling before the car actually runs out and reinforces the more pessimistic range readings shown at the same time. --- Have I been thinking about this too much? Link to comment Share on other sites More sharing options...
ghemmings Posted January 21, 2007 Report Share Posted January 21, 2007 I think you've hit the nail on the head NikW. I hadn't thought about the fuel sender float hitting the bottom of the tank when moving. Makes soooooo much sense (assuming it is a float type level sensor?). Link to comment Share on other sites More sharing options...
alera Posted January 23, 2007 Report Share Posted January 23, 2007 Wow I only get around 320 miles per tank on my 3.7 in sport mode driving it hard. I only do very low mileage though... However I fill it up again when range gets to around 10 miles, the emergency reserve is probably up to 50 miles driven economically so to get it down to fumes it would probably be doing going on 400 miles a tank driven hard.... Link to comment Share on other sites More sharing options...
Davyd Posted February 7, 2007 Report Share Posted February 7, 2007 Most miles seen? How about 960! Filled up in Oldham - up over Saddleworth Moor to join M62 eastbound, in the words of the song, 6 lanes moving slow and the magic 960 showing just before the A1 junction - I was devastated when it fell to 770!? as i got onto the A1 Southbound. Best per tank about 520 but that is cruise control all the way. Filled up with 5 miles showing but still only got 84 liters in. All figures are for my 3.7 sport. Davyd Link to comment Share on other sites More sharing options...
garcon magnifique Posted February 7, 2007 Report Share Posted February 7, 2007 That's quite impressive - especially considering the hill you have to haul it up out of Oldham! Often wondered what the real range of an A8 3.0TDi is - could be a serious 'sensible car' option in a couple of years. Link to comment Share on other sites More sharing options...
niazS8 Posted February 7, 2007 Report Share Posted February 7, 2007 Getting between 12 - 15 mpg round town, so say about 220 per tank. Max I've seen is 450 on a steadish motorway run. Recently I have had a play with fuel settings and have changed this from 100 to 105, hopefully this will improve the accuracy of the DIS readout. Me thinks. Never get chance to switch to cruise too many pr.cks in the way. Link to comment Share on other sites More sharing options...
garcon magnifique Posted February 7, 2007 Report Share Posted February 7, 2007 You can set cruise at speeds under 100mph y'know... Link to comment Share on other sites More sharing options...
niazS8 Posted February 7, 2007 Report Share Posted February 7, 2007 [ QUOTE ] You can set cruise at speeds under 100mph y'know... [/ QUOTE ] or in my case at 30mph Worst thing I usually get undertaken and overtaken at the same time!!!! Link to comment Share on other sites More sharing options...
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