VW Polo Bluemotion low mpg

Flearoy

vax2002 wrote: »

Urban myth, no engine needs to be "bedded in" these days.

I don't work in the automotive industry but from my very limited experience, diesel engines do seem to be a bit tight when brand new, loosening slightly with improving economy over a few thousand miles. I know modern manufacturing techniques are light years ahead of the olden days when cars had to be 'run in' properly with different oil even to start with, but all the same, I find it surprising to hear that manufacturing tolerances are so tight that no initial wear/smoothing of bores and piston rings will occur on a new car. Big respect to the engineers/robots if it is the case! Mind you, my diesels were Renaults from the 2000's

Hammyman

Loganfire wrote: »

so a new engine does need to be bedded in then? and if so how many miles would you say this takes

Maybe 5,000 or so. On bigger diesels its over 10k.

vax2002 wrote:

Urban myth, no engine needs to be "bedded in" these days.

By bedded in, they mean "loosened up", not the traditional way we used to do with the old Ford Capris, Escorts, Anglias etc where you built up engine speed and load over the first 500 miles.

almillar

Re: MPG figures. You've got an urban cycle (town driving), extra urban (out of town) then combined (average the two I think). What are the figures for the car you had before? And what did you actually get? If you drive long distances all the time you might pay attention to extra urban, but if it's mostly short journeys you do, you should be looking at urban. If your current driving gets 10% less than combined, you can expect to get 10% less than the combined figure for any other car, if you keep driving the same way.
No matter what you say, that car DID get that figure on that test. If the salesman promised that figure to you, that's a different story. If you do a lot of short journeys, your engine is never properly up to temp, and you'll never get those figures.

anotherbaldrick

almillar wrote: »

Re: MPG figures. You've got an urban cycle (town driving), extra urban (out of town) then combined (average the two I think). What are the figures for the car you had before? And what did you actually get? If you drive long distances all the time you might pay attention to extra urban, but if it's mostly short journeys you do, you should be looking at urban. If your current driving gets 10% less than combined, you can expect to get 10% less than the combined figure for any other car, if you keep driving the same way.
No matter what you say, that car DID get that figure on that test. If the salesman promised that figure to you, that's a different story. If you do a lot of short journeys, your engine is never properly up to temp, and you'll never get those figures.

Incorrect . The OP's car has never been officially tested . What was tested was a car of that make and model , carefully tuned and honed by the manufacturer to ensure that it gave ultimate results in the tests. The manufacturers specifically say that it is only a guide and not to be taken as a guarantee that your particular vehicle will get anywhere near it.

caeler

Hi I'm in the same boat. I've just taken delivery of Audi's version of the bluemotion, it is 99 co2 with an expected combined mpg of 74mpg so I'm expecting great things. However to get those great things you need to drive so very differently! I'm told that the cold weather will impact my mpg plus until the engine losens up after a few thousand miles. My first tank got me 65mpg (I manually worked this out as well as using the computer to monitor usage). You need to feather the throttle, coast down hills, no speeding up quickly, drive slowly to achieve anything impressive. The highest I've got my car to is 73mpg but average on a journey is between 60-65mpg. I'm monitoring it all closely! My old car used to manage 45-50mpg so this is still really good!

Loganfire

caeler wrote: »

The highest I've got my car to is 73mpg but average on a journey is between 60-65mpg. I'm monitoring it all closely! My old car used to manage 45-50mpg so this is still really good!

I would be happy with your results, and yes I am still on my first tank of fuel just but my mpg is like 40 percent down on the manufactures. When it comes to driving I am do what people are advising me to do.

Trebor16

Loganfire wrote: »

I would be happy with your results, and yes I am still on my first tank of fuel just but my mpg is like 40 percent down on the manufactures. When it comes to driving I am do what people are advising me to do.

Are you going by the trip computer?

Ranger8

Its all down to your driving, the engine will give a few extra mpg when its got a few miles under its belt but more often than not its how the car is driven which counts. :cool:

ROY47

As has allready been said , driving style effects the mpg

My wife's fiesta diesel ,with her driving for a week ,school run , shopping etc. according to the computer in the car shows 49.7 mpg tested over the last few weeks on an average week

Last week I was off work on holiday ,she was ill so I did school run shopping etc.

I reset the computer on monday last week , read it on friday ........................... 57.9 mpg with me driving

women drivers

Altarf

Weird_Nev wrote: »

As already stated the 'combined cycle' is a very specific test, they run the car on a rolling road through a defined series of speeds, accelerations, decellerations. It should be treated as a mere indication of a cars efficiency.

Actually the 'combined cycle' is just the average of the 2.5 mile 'urban' cycle, and the 4.3 mile 'extra-urban' cycle, adjusted for distance, but you are right that it is a *very* specific set test.

As for replicating 'real world' driving, the test is done at 25C (and the car has been warmed up to that overnight), the urban test averages 11.5 mph and the extra-urban "motorway" test averages 39mph, and as for acceleration, 0 to 60mph takes 60 seconds.

So provided that you only drive like a nun on a warm summers day, then you might get close to the official mpg. Might.