[Pikapolonica]

Last week due to the cold mornings, I my heater up to max (31°C).  I had to fill up yesterday and noted that I only got just over 500km on one tank.

Is this normal or do I have a problem?

I've been averaging 800km on a tank.

[Waja]

I'm pretty sure that thumper said that fuel economy was affected quite alot during the winter/cold days due to the cold air on the intercooler and so he made a cover that he used during the winter (this is all by memory...) and supposedly it was effective at decreasing fuel consumption..

i've also noticed it too with my fuel economy dropping (but not as much as yours!!)

[Dazzler]

I'm pretty sure that thumper said that fuel economy was affected quite alot during the winter/cold days due to the cold air on the intercooler and so he made a cover that he used during the winter (this is all by memory...) and supposedly it was effective at decreasing fuel consumption..

i've also noticed it too with my fuel economy dropping (but not as much as yours!!)

 

The fuel economy difference in cold weather isn't huge (from my experience only 10% worse or less)

Covering the intercooler with a piece of plastic sheet or cardboard is very risky unless you have something like a scan gauge  to monitor temperatures at various points in the engine.

Pika I'd just monitor it over the next couple of fills..if it is driving normally it is unlikely you have a problem...

Hi all,

Well, I beg to differ here.  I am finding it easier to get low fuel usage in cooler weather.  I'm not talking about sub zero temps, but rather temps from 0-10 degrees C.  I rairly experience temps lower than -4 degrees C.  When the temps are in the high 20s onwards, my expereience is that the fuel economy is not as good.  I have also watched the effectiveness of the intercooler and have found that the intake air temp markedly increases in warmer weather, having a detrimental effect on the fuel economy.  I must concede there may be some increase in fuel usage in extreme temperatures due to the a/c working harder.

I believe the reason for my findings is that cooler air is denser air and diesel motors produce more power when the intake air is cooler.  Why have an intercooler if this were not the case.  I tried the cardboard over the intercooler and never noticed any improvement in fuel economy when the temperatures were 0-10 degrees C.

These have been my findings.  I must emphasize that I am not talking extreme sub-zero temperatures. 

Others may not agree.

Bob

[Dazzler]

Hi all,
Well, I beg to differ here.  I am finding it easier to get low fuel usage in cooler weather.  Others may not agree.
Bob

 

Hi Bob...

We seldom get the high temperatures you get in S.A. but very hot temperatures (say 30+) seemed to have the same effect as say less than 5 degrees for me .. a slight decrease in economy..

You get amazing economy day in day out (which I "blame" on your nice flat roads)  Maybe it is more noticeable when , like me you are getting mid to high fives....

[bumpkin]

I certainly noticed a big difference in the petrol model in sub zero temps, one of my readouts over the winter was 28.3mpg

[eye30]

Yes.
Here where I live during the colder months, well in fact all 12 months, fuel useage goes up.

Presently my read out shows 51 to 54 mpg but in cooler months this showed 48 to 51 mpg.

[Lakes]

well i don't cover my intercooler now, but i did after reading thumper, i never saw a gain covering it when temps were really cold, so could not be bothered now. i just did a trip from syd to melb & back, saw temps as low as 2c average temp seemed to be about 15c to 18c. have not worked out economy yet but very happy.
what i have learnt is there is no magic no tricks, simple fact on getting good economy is how you drive. drive fast you use more fuel drive slower you use less fuel, just have to find happy medium. from syd to melb on coast road i covered just a few k's over 1,000k and could only get 44L into the tank to fill to top this is stock as a rock CRDi