69mpg from 1.6tdi surely not !!

[rji]

adamb87,

You are correct, that is what Seat say. But the official tests are carried out on a vehicle with 1,800 miles. If you have to wait until the 2nd service at 20,000 miles and then see IF you get the economy it is clear that the test vehicle was definitely NOT a standard production vehicle with 1,800 miles.

wait until my second service and see what the crack is then

That's got be the best line of fobbing-off I've ever heard.

I cannot believe that manufacturters are allowed to sell a product and then say that you have to wait 2 years before it might become what you paid for.

I was told that the Technical Unit would not consider looking at it until it had 8,000 miles. So if there actually is a problem that could be fixed it will not be found (and there is a noise from the engine that shouldn't be there). It is now clear that at 8,000 miles they willl change it to 10,000 miles and then 20,000 miles.

Seat Finance claim that each vehicle will be different (but Conformity of Production is a requirement). They claim that you are unlikely to achieve the official figures. There are an infinite variety of driving styles etc. etc...

To my mind they are not saying that you will get good economy when it is run-in. They are throwing up an "infinite" number of excuses as to why your not going to. They are saying it is possible that you will never get good economy. And that they don't have to (or can't) do anything about it. Their response gives me no reason to have any confidence going forward.

The official tests are done at 1,800 miles. Their marketing doesn't say it will be crap for the first 20,000 miles or that your car might be built differently from the one they tested. It doesn't say buy one and wait 2 years to see if you got lucky. There are people with high miles on their cars that still give very poor economy.

adamb87 I understand what you are trying to say and I appreciate the support. But I started driving diesels 25 years ago and have driven mostly diesels for the last 11 years and this really is the worst of any of them.

 

[adamb87]

It may have been fobbing off but on mine the mpg has drastically improved as the miles have clocked up. Hope you get something sorted bud

 

[Generic]

I get awesome MPG (according to the computer) during the first 100 miles. I.e. My computer will read 425 miles remaining after 100 miles covered on a full (non-vented) tank.

After that 100 miles the MPG on the clock stays high (50-60), but the range drops around 40-50 Miles per 20 mile journey.

Hence why my actual consumption is so much higher than what the computer states. Generally my computer is between 8 and 12 MPG higher than the real MPG (see my sig). Just seems as though the computer has been left in "sales mode".

 

[adamb87]

Well quite often If I add up my trip to my range the highest I have seen that is about 615 miles. But keeping it ther is impossible lol

 

[rji]

The Miles Remaining is calculated using the current level of consumption. The Fabia uses the consumption over the previous 50km so the Ibiza might also use the previous 50km.

If you had been getting 60mpg for the 50km before you filled the tank then the Miles Remaining after filling would be calculated as: 60mpg times the fuel remaining (approx 10 gallons) = 600 miles. To get the 600 miles you must continue to average 60mpg for the whole tank.

But also remember the trip computer's mpg calculation might be rather optimistic. Mine reads 10% high. So an indicated 60mpg in reality is about 54mpg so the Miles Remaining should really be 540 miles and not 600 miles.

 

[adamb87]

I have calculated the mpg myself brim to brim and it appears to be pretty accurate.

 

[rji]

adamb87

I have calculated the mpg myself brim to brim and it appears to be pretty accurate.

Then all you have to do is keep your average consumption up to 60 mpg for the whole tank full (that's the hard part) and you'll get your 600 miles.

The new Passat 1.6 TDi CR with blue-motion "can take you up to 1,000 miles on a single tank".
New Passat 1.6 TDi CR Blue-Motion:
Combined cycle 65.7mpg, tank capacity 15.4 gallons, range 1,011.8 miles
Ibiza 1.6 TDi CR:
Combined cycle 65.7mpg, tank capacity 9.9 gallons, range 650.4 miles

Many people find their trip computer to be fairly accurate. When it was new mine was reading over 15% high. Now with 4,500 miles it's reading about 10% high. I don't expect it to be spot-on (it's still a useful guide) but I don't know why it's so wrong or why it has changed.

 

[Biker]

On the subject of the trip computers accuracy, I have done a little test on my last tank of fuel. Filled the tank right up and reset everything.

After 591.4 miles, I filled up again and got 42.29 litres in. I work that out to be 63.5 MPG.

The trip computer worked it out to be............ 61.8MPG

 

[adamb87]

Thts pretty good. I will work mine out again the next time i fill up. I not ever got to 590 miles though, had it estimated but never seen it.

 

[R22 JGB]

On the subject of the trip computers accuracy, I have done a little test on my last tank of fuel. Filled the tank right up and reset everything.

After 591.4 miles, I filled up again and got 42.29 litres in. I work that out to be 63.5 MPG.

The trip computer worked it out to be............ 61.8MPG

61.8 is a lot different to the 73mpg you posted elsewhere.

Having said that I can get 200mpg on mine!!


Provided I use the instantaneous readout and only go downhill!!

 

[Biker]

61.8 is a lot different to the 73mpg you posted elsewhere.

Correct mate there is quite a difference in those two figures, as there was quite a difference in the driving style that produced them.

The 73mpg was a quiet Sunday afternoon drive and the other was a frantic dash to the other end of the country. Given how I was driving, I was amazed to get the figure into the 60's.

But on that note, if my computer is reading low was the 73.4 really 76.1!

 

[rji]

Just for comparison, Biker said

After 591.4 miles, I filled up again and got 42.29 litres in. I work that out to be 63.5 MPG

591.4 miles on one tank! You lucky, lucky, lucky, lucky !

In December I put in 42.28 litres to fill the tank. I had done 374 (careful) miles since the previous fill. I work that out to be 40.2 mpg. The ever optimistic trip computer number 2 was reading 50 mpg.

In a 2.2 petrol 407 Sport I got 499 miles out of a tank but it took 63.63 litres to fill it giving 35.65 mpg. The official combined cycle figure was only 31.4 mpg. Our overall average for the time we had the car was 31.7 mpg. At least my 1.6 TDi Ibiza is doing better than that.

 

[Stebb]

Watching this thread with interest, as the owner of a 10 plate 1.6TDi....

I got 612 miles from the last fillup to the bong, and it told me I had 55 miles left to go.
This figure has notably improved over the last week due mainly to the temperature outside being better and not having to de-ice the car before driving off, which makes sense I presume.
I have found however, that regardless of fuel source i.e. Asda or Morrisons, on occasion I can get what seems like another gallon or so in the tank after the first pump shut off, other times the diesel is visible in the filler pipe neck almost immediately. I always get more miles from the tank if I've been able to get the extra in.
Does the tank have some sort of hump or airspace in it?
Perhaps I should try rocking the car next time - at least it'll keep the other motorists amused!

 

[adamb87]

Well apparently there is an expansion tank to which there is a button at the right of the tank. I have never tried this yet but I have heard you can do another ten litres in it. Dont do it on a hot day tho lol. Do it if you are doing a journey straight away. Like you have said though I have also noticed a difference with the milder temperatures. I have got my second service so again may see another Improvement after that.

 

[Trotski]

there is a theory about fuel and temperature, if you fill up early in the morning, after a cold night the fuel will be denser, as it's pumped and measured by volume, you get "more" in, likewise if you fill when the tanks have warmed up, late on a summers day say, the fuel will be less dense.... therefore less effective and as above you get "less" in

 

[Stebb]

Hi,

A difference of 10 litres sounds to be in the right ballpark to what I have experienced, so some sort of reserve or expansion tank is a reasonable answer - I take this is supposedly not normally 'available' unless I've triggered a vent opening or something. I've taken a look and not seen a button anywhere, unless the pump filler nozzle presses something when it's in at a certain angle (I never worry that the pump is on the wrong side of the car to the filler as the pipe always reaches, but would mean the nozzle is upside-down).

I can agree that fuel densities and measurements etc., are connected to temperature, but I think the differences seen are more likely to be shorter warmup times. This is seen be the heater kicking in almost straightaway lately, rather than after 10 or so miles. That said, do we have sticking thermostat problem!?!

 

[adamb87]

Well I think filling up expansion tank has made an impact. Probably due to the computer taking extra fuel into account. Making me wonder if seat did this to claim the mpg figures ??

 

[nightflight]

Must be something in the air, mine's averaging 48.2mpg over 512 miles.
cruised to york and back today at a steady 58mph (tomtom) and averaged 62/63mpg door to door.
If only it'd keep it up

 

[rji]

nightflight

cruised to york and back today at a steady 58mph (tomtom) and averaged 62/63mpg door to door.

I don't like to be a party pooper but on a continuous steady run you should be getting somewhere in the region of the Extra Urban Cycle figure (78.5 mpg). In other cars we could easily exceed the Extra Urban Cycle figure for a single continuous journey by taking it steady, but sadly not in the Ibiza.

Your average over 512 miles, depending on the type of journeys and driving, should be in the region of the Combined Cycle figure (65.7 mpg) whereas it's actually less than the Urban Cycle figure (52.3 mpg).

If your trip computer reads 10% high (like mine) then your 48.2 mpg is actually 44 mpg and your 62/63 mpg is only 56 mpg. Check the accuracy of yours by calculating your mpg from full tank to full tank. You never know, yours might be reading low.

 

[R22 JGB]

The tank on the Ibiza can be "vented" during the filling process this allow another 10 litres or so into the tank.
The foto shows (not to well) the vent plug at 3 o'clock in the filler tube

To fill & vent the tank, insert the fuel nozzle as normal and hold the lever until it clicks, this is normally around 45 litres from an almost empty tank , now withdraw the nozzle and place it just in front of the nipple in the filler neck, if you gently push the nozzle, the nipple will come off it's seat and swing into the filler neck and will vent the top of the tank, hold the nozzle against the nipple and you should be able to get another 10 litres or so into the tank., dont try to fill too quickly as the air escaping from the tank can blow the fuel back at you.
The vented area you have just accessed is provided by the manufacturer to allow a full tank of cold fuel to expand on a hot day, obviously you have just used that expansion space, so DO NOT do this if you are going to fill the car then park up, as on a hot day the fuel will expand.

I've just topped my car up with 54.17 litres of fuel.

Obviously venting the tank has no effect to fuel economy, it simply allows you to travel further between fill ups. The gauge will stay in the full position for around 200 miles!
This is the way I have filled my car since 565 miles, I brim every tank, the divide the amount of fuel used by the distance since the last fill to accurately gauge the fuel consumption of the car.