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I'm up to 1800 miles now and averaging 36-37 mpg on my mainly motorway commute (70-95mph), up on the 32-33mpg it did when it arrived, obviously the engine is loosening off a little.
 

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Good to hear it improves over time - at 800 miles I'm still getting about 28mpg!
 

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I am up to around 1500 miles know. Just drove from Germany to Scotland via Holland (overnight ferry). Got to be careful with your speed in Holland - fines are very hefty. Sat at an average of 69mph for over 120 miles. MPG actually reached 41MPG at one stage and levelled out at 39.8 MPG for journey. Don't normally achieve this as I normally cruise at around 115mph when limits permit.
 

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Best I've done is 44mpg over my daily 55mile (each way) commute from west of Glasgow to Edinburgh via the M8 (averaging around 55 mph).

That's after around 4000miles on the clock.
 

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It does respond well to quite fast speeds on the motorway. Sadly, I do not get many opportunities for motorway driving and consequently mine is returning about 35mpg.
 

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Fuel economy is one of the issues that my dealer is looking at for me this week. On long motorway runs I struggle to get over 30mpg (speed between 60-70mph). The dealer has a theory as to why this might be so i'm hoping this problem is fixed when I pick the car up next weekend. Around town I get around 25mpg at the moment.
 

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Roma said:
Fuel economy is one of the issues that my dealer is looking at for me this week. On long motorway runs I struggle to get over 30mpg (speed between 60-70mph). The dealer has a theory as to why this might be so i'm hoping this problem is fixed when I pick the car up next weekend. Around town I get around 25mpg at the moment.
Roma, who says? Is the consumption figure derived from your calculation, or the cars average MPG calculator :?:
 

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I reset the 'A' trip computer at every fill-up. I then note the average over an entire tank of fuel. Granted it'll be slightly out but it shouldn't be out by much.
 

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Roma said:
I reset the 'A' trip computer at every fill-up. I then note the average over an entire tank of fuel. Granted it'll be slightly out but it shouldn't be out by much.
Have you considered doing the maths, or math if you an American reader, because it is possible that the computer is faulty. After Jaguar Assistance did an Hard Reset on my car the fuel consumption monitor started to produce different and better figures than hithertoo. :)
 

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pekem said:
Roma said:
I reset the 'A' trip computer at every fill-up. I then note the average over an entire tank of fuel. Granted it'll be slightly out but it shouldn't be out by much.
Have you considered doing the maths, or math if you an American reader, because it is possible that the computer is faulty. After Jaguar Assistance did an Hard Reset on my car the fuel consumption monitor started to produce different and better figures than hithertoo. :)
I'm hoping that me dealer will rectify this issue this week. He has my car in all week with the list of my issues and he's hoping to fix the majority of them.
 

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Mileage.... 4,700 returning 35.5 from new & approx 37 on motorways.
has certainly improved over the last 1,500-2,000 miles.
Be interested to know if anyone has noticed any dramatic reduction when using air con. ??
 

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sodgob said:
Mileage.... 4,700 returning 35.5 from new & approx 37 on motorways.
has certainly improved over the last 1,500-2,000 miles.
Be interested to know if anyone has noticed any dramatic reduction when using air con. ??
Should that be "when not using air con"
I have just realised that I have never turned mine off, it would be interesting to know if it makes a difference; or perhaps that should be, how much difference does it make since it is bound to.
 

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I'm sure it does make a difference, i have not had mine on for any lengthy periods for some time now & wonder how much improvement can be attributed to this .
guess the only way to find out would be to leave it on for 1,000 miles & check the consumption again.
 

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sodgob said:
I'm sure it does make a difference, i have not had mine on for any lengthy periods for some time now & wonder how much improvement can be attributed to this .
guess the only way to find out would be to leave it on for 1,000 miles & check the consumption again.
Well I watched the Channel Five car show tonight and they were suggesting that many people could achieve a 10% fuel saving by ensuring correct tyre pressures. They went on to talk about throwing overweight passengers out for another 10% but did not talk about the aircon, how shallow is that? However, on the basis of what they did say I would not be surprised to learn that a 10% improvement would come from switching the air con off.
 

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Am i right in thinking it is not necessary to have the air con switched on all the time, but it needs to be on occasionally to keep the gas moving ??.
if so.. i have never quite known 'how' occasionally.
 

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sodgob said:
Am i right in thinking it is not necessary to have the air con switched on all the time, but it needs to be on occasionally to keep the gas moving ??.
if so.. i have never quite known 'how' occasionally.
Occasionaly = Once a week.
 

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Vapourgrey said:
sodgob said:
Am i right in thinking it is not necessary to have the air con switched on all the time, but it needs to be on occasionally to keep the gas moving ??.
if so.. i have never quite known 'how' occasionally.
Occasionaly = Once a week.
I am sure you are right about the need to turn it on from time to time. I turned it on when new and have never turned it off; just leaving it on auto and adjusting the temperature from time to time. Don't know if I am doing wrong or not. Probably need to read the book :eek:
 

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The same here Roma, my consumption is c**p, it had imporved a bit to 34-35mpg and now back to low 30s (after 4,500 miles).
It could be a faulty trip computer but the tank doesn't lie. I was getting 480 miles from a fullt ank whne I bought it, then it went up to 520 but now back to around 500.
In any case, nowhere near the 575 miles as per the brochure...

My car isa going to the dealer next Wednesday for 3 days and they will look at the faulty Bowers and Wilkins stereo (not much sound from the rear), the noisy seat belt tensioner, the stains on the upholstery (since delivery) and the door seals (driver and rear passenger).
See what they can fix!
I'll keep you all posted.
ck
 

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ck1 said:
The same here Roma, my consumption is c**p, it had improved a bit to 34-35mpg and now back to low 30s (after 4,500 miles).
It could be a faulty trip computer but the tank doesn't lie. I was getting 480 miles from a fullt ank whne I bought it, then it went up to 520 but now back to around 500.
In any case, nowhere near the 575 miles as per the brochure...

My car isa going to the dealer next Wednesday for 3 days and they will look at the faulty Bowers and Wilkins stereo (not much sound from the rear), the noisy seat belt tensioner, the stains on the upholstery (since delivery) and the door seals (driver and rear passenger).
See what they can fix!
I'll keep you all posted.
ck
It is interesting that at the outset you did not expect the figure to be much better than 33/34 which you were getting. More interesting you then lowered the tyre pressure and have since reported a decline in the consumption figure. I suspect that you were right to lower the pressure but it would be interesting to discover if there was a connection and to what extent tyre pressure impacts on the consumption :?:
 

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I have done 4,600 and am getting 35.4 mpg and a range on a full tank of about 515 - 525 miles. The mpg could well be affected by tyre pressures, air con usage, other gadgets plugged into the lighter etc.

I have been trying to stay below 75 on the motorway as when you reach 80 or more the consumption does fall away quickly.

You can bet the Jaguar official mpg was worked out when they had no air con on, no gadgets, no sat nav on or radio and probably someone of Ronnie Corbett's size driving!
 
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