Hi all I have a 1.6 Superb SE (not the greenline) and I am getting some wierd MPG variations recently.

It has covered about 14,000 miles in the last 8 months and generally the economy has been good. Just under 40 mpg on my 10 mile commute to the office (when averaged over a week) and up to 55mpg ish on a motorway run when driven normally.

However over the last week or so, I have noticed that the MPG is dropping a fair bit and only got 27 mpg out of it on the comute the other day. On motorway runs it is getting harder to keep it over 50 mpg.

Now I know a lot has to do with driving style, and I generally put my foot down when required, but I equally do keep an eye on MPG and try and save where I can.

Any thoughts about what to look for? I am loathed to take it to a dealer just yet as I doubt anything is acutally wrong and I am sure I would get fobbed off.

Any suggestions would be welcome (e.g. bad fuel, cooler temps, needs a service etc)

Thanks

The 40 mpg was good if you got that in the cold weather, after all your Engine oil is only up to temperature at around 10 miles before parking, then the same again coming home.In the winter,

the Ambient temp was lower, heater on & rear screen, lights and radio maybe.

You drive a bit slower.

If its been warmer in the last couple of months that would be quicker in your oil getting up to the 80-88 degree celcius.

You would expect as good if not better MPG over the 10 miles.

?So are your tyre pressures correct, the Air filter clean & the car sound like its running fine.

Same fuel being used?

Are you using the A/C on now,

and just driving a little quicker than in February, March, April & maybe stopped just a little bit more at junctions.?

It all costs in fuel consumption.

george

Sorry I should have said it is the 1.6 diesel.

Does it need to Regenerate?

I had a Peugoet Bipper that was good for 50-60 mpg when i drove it.

When i got it back after others using it the fuel was gone because it had been into Regeneraration in the few days it had been away from my keeping.

PITA.

george

Hi all I have a 1.6 Superb SE (not the greenline) and I am getting some wierd MPG variations recently.

It has covered about 14,000 miles in the last 8 months and generally the economy has been good. Just under 40 mpg on my 10 mile commute to the office (when averaged over a week) and up to 55mpg ish on a motorway run when driven normally.

However over the last week or so, I have noticed that the MPG is dropping a fair bit and only got 27 mpg out of it on the comute the other day. On motorway runs it is getting harder to keep it over 50 mpg.

Now I know a lot has to do with driving style, and I generally put my foot down when required, but I equally do keep an eye on MPG and try and save where I can.

Any thoughts about what to look for? I am loathed to take it to a dealer just yet as I doubt anything is acutally wrong and I am sure I would get fobbed off.

Any suggestions would be welcome (e.g. bad fuel, cooler temps, needs a service etc)

Thanks

I get those or better mpg in my car (4600 miles), so you should get at least that.

I find the mpg drops a bit at the end of summer and into autumn when the air temps are lower. That takes a few mpg off the fuel efficiency. Also, as another poster said, it's worth checking the tyre pressures as that can take 5 mpg off easily if one or some have fallen.

Thanks for the info. The tyres look ok, but I will check them tomorrow just to be sure they are spot on.

I do have a couple of long trips coming up so I will keep and eye on it.

I'm getting 60mpg average (similar journey's) from the Greenline and not suffered a regen that I've been aware of but it sounds like that might be what has happened to you.

I find the mpg drops a bit at the end of summer and into autumn when the air temps are lower. That takes a few mpg off the fuel efficiency. Also, as another poster said, it's worth checking the tyre pressures as that can take 5 mpg off easily if one or some have fallen.

I think the lower mpg also comes from all the additives that stop diesel fuel waxing in cold temps but I don't know what sort of date these fuels are distributed.

In Scotland the Winter fuel comes out to the Filling Stations from around the 16th October - 15th April.

Down south may be later & stopped earlier.

Anti Waxing additive should not reduce your Fuel Consumption. That is with Diesel.

(And Petrol might be of better Octane as a Winter Formulation, better than minimum Octane the rest of the year)

Slower speeds in cold weather should improve fuel consumption.

Slower warming of oil might reduce it on short journeys

Warming the car, De icing, heated mirrors, rear screen heater, etc might reduce it.

Swings and roundabouts really.

Tyre pressure should be put higher in cold weather, not lower.

george

Tyre pressure should be put higher in cold weather, not lower.

Tyre pressure should be set to recommended pressure, irrespective of ambient temp

Sorry ,

you are of course Correct,

& 'Winter/Cold weather tyre' pressures will be most likely recommended as slightly higher,

so best check the tyres manufacturers recommendation and not just the Vehicle Manufacturers.

& your tyre pressure as set now if you do it by BAR will possibly show lower as the Ambient temp drops, so check your pressures when the weather is lower, so that they are correct.

I made a rather sweeping statement and should of explained better.

Do not go on the widely help belief that Lowering your tyre pressures will give better grip in Cold or Snow.

Thats a getting out of being stuck type situation,

then you re-inflate your tyres. Or they may overheat.

Low pressures can cause overheating, especially when using Cold weather tyres.

http://www.michelin....ld-weather-tips

george