Poor fuel consumption on a new Kia Rio diesel

[ItsOnlyMe]

Hi,
I have a new Kia Rio 1.5 diesel. It has done 2,000 miles and yet I am only getting an mpg of less than 50mpg. I live in quite a rural area but predominently A roads and have been driving sensibly, and not in a city/town.

The quoted Urban (cold) mpg is 52.3, and the combined 62.8.

Is it worth a call to the garage or is this just the norm. I know I can't expect to get the quoted figures but expected to get somewhere near the combined figure, not less than the Urban one!

[thescouselander]

Are your tyres at the correct pressure?

[ItsOnlyMe]

yeah I have checked tyre pressure and it is ok.

[thescouselander]

The only other thin I can think of is binding brakes although I would be surprised if this happened on a new car.

It could be that you need to wait for the car to run in a bit and loosen up - its possible you might see the MPG improve with more miles. It could be worth asking the dealer about it anyway.

[ItsOnlyMe]

yeah I will maybe go along and see what they say about it just don't want them to look at it and then charge me anything!

I was unsure whether the running in argument was a myth or not.

[Crabman]

Originally Posted by ItsOnlyMe

yeah I will maybe go along and see what they say about it just don't want them to look at it and then charge me anything!

I'd think as it's a new car (thus under warranty ) you shouldn't be charged anything full stop!

[Inactive]

It could possibly be because the engine is still tight at 2000 miles.

[leehal]

In my experience from owning several diesels over the years you won't really notice anywhere near the quoted figures until 10,000 miles - I would also take the official figures with a pinch of salt. Again from my experience I would knock around 10% of those.

[Hintza]

I agree with the last two comments. Get some more miles under your belt.

How are yoy calculating mpg? On board computter or pencil and paper after a fill up?

If not the later fill car drive till you need to fill up and do your calculations then.

With my heavy foot if I get within 20% of quoted figures I would be over the moon...

[ItsOnlyMe]

Thanks for replies.
You seem to have cleared up that 'new car requiring run in' is not a myth, which I thought with modern technology was no longer required.

pen and paper method for calculating mpg as it has no computer

[Keith]

Remember the quoted figures are gained under test conditions, not in real world driving.

[Inactive]

Originally Posted by ItsOnlyMe

Thanks for replies.
You seem to have cleared up that 'new car requiring run in' is not a myth, which I thought with modern technology was no longer required.

It is not strictly " running in " that was a period of gentle use in the first few hundred or so miles, in days gone by, it is really wearing in, modern vehicles are made to very tight specifications, and they don't loosen up fully until around the 4/5000 mile mark in my experience.

Things should improve with miles..

[leehal]

Originally Posted by Inactive

It is not strictly " running in " that was a period of gentle use in the first few hundred or so miles, in days gone by, it is really wearing in, modern vehicles are made to very tight specifications, and they don't loosen up fully until around the 4/5000 mile mark in my experience.

Things should improve with miles..

Diesels seem to need more 'running' in that petrol engines, you may find that your car drinks alot of oil in the early stages too.

Another thing to remember with regards MPG is diesels are more efficient in warmer weather.

[vikingaero]

50mpg is good for a new engine diesel. If you're comparing your mpg with the manufacturers/EU stated mpg then you really need to knock 10mpg off their figures to be realistic. I'm fairly sure that the EU mpg test is held on a rolling road in a warehouse with no wind resistance!

[geo555]

You can read this article about how the MPGs are caculated and why you wont achieve the same results yourself.

http://driving.timesonline.co.uk/tol...cle2214542.ece

[AdrianHi]

I think the points have been made above now. Expect to fall short of official combined figures by possibly as much as 8%-10% anyway. If you do get the official combined figure (I almost am on my 34,000 mile diesel with similar driving conditions to you) it is likely to be in outside temperatures of around 10-17DegC when no heaters or aircon is required.
38mpg (winter and urban driving) to 53mpg (spring and casual motorway driving) is the range I see.
You need more miles on the car before you start measuring MPG.
Now that you are past the initial 1000 miles make sure you get the revs up near the red line several times a week to loosen the engine up so it can reach it's best performance and economy in time and not become a real oil burner.
In the first 8000 miles or so, as suggested above, watch the oil level like a hawk (every 1000 miles). Mine oil level went - 1000 miles on max, 3000 miles on max, 4000 miles on max, 6000 miles just below minimum!!!! All checks done on the flat with a cold engine. This is a fairly well known phenomena. My car uses hardly any oil now.

I think if you can get 55mpg out of it when you have 8000 miles and the right weather you will be doing well. You will probably notice the engine loosen up and improve a bit more as you go through the 10,000 to 20,000 miles range.

Also use BP Ultimate Diesel if you can find it no more than 6% more expensive than regular diesel. Millers Diesel Sport 4 additive in regular diesel is a good alternative (I've been using it for quite a while now.)

[murphwiz]

The Rio diesel usually starts getting much better consumption after around 10k, 55mpg is around what chap at work gets out of his.