Is the weather affecting my fuel economy?

GrahamR

Member
With the current cold spell (it's rarely been above freezing for the last two weeks in Aberdeen) I'm only getting about 42 mpg on my TDi. In the summer it's usually well above 50.

Does everyone else find the same?
 
I normally get around 50mpg in my 75bhp tdi se. This last fill up, for the last 3 weeks, I only got 36mpg (243 miles) I dont have computer so work it out. Best I have ever had is 60mpg, 380 miles, in the summer.
 
Quite normal to loose economy in cold weather. Mine has gradually dropped from 54 ish to 51 ish and last week when the weather was very bad only 48.
 
Most of my journeys are long (150 miles) and I find that the weather affects my mpg very little. In fact when it was very bad (snowing) I had to slow down and got an extra 3mpg and achieved 65mpg.

But in my wife's Smart car where we do more short journeys we get very roughly 45mpg in the winter and 55mpg in the summer. Some of that is due to idling the engine in the morning whilst scrapping off the ice.
 
Hi all,
Mines taken quite a pounding mpg wise,
Im down to 42 mpg with an average speed of 18 mph.
That is including starting it up to let it thaw out a bit before I take to the highland roads.

All you valet types had better not read this,I havent washed it in months as the Dirt will keep the salt off the paint :p:cool:
 
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Winter Fuel Consumption

My A2 1.2 TDI's fuel consumption increases from over 100 mpg in the summer to about 90 mpg in the winter. In very cold weather it takes about 15 miles for the temperature gauge to reach 90 C. When driving in town the temperature gauge quickly drops back down again as so little heat is wasted. Surprisingly the auto stop-start system operates in cold conditions even if the engine hasn’t warned up yet.

If ECON on the climate control is turned off (Auto on) the engine electrical pre-heater operates automatically below 5 C. This uses additional fuel even though the air-con compressor does not operate. This applies to all TDIs.

The heated rear window also uses approximately 1 litre of fuel every 10 hours.

I am considering using lighter synthetic transmission oil to see if it reduces consumption in the winter.
 
My economy is worse at the moment too even though Ive just put on the aero bits! Winter diesel is also formulated differently which may have an impact. Incidentally my temp gauge didnt even get to 90 on a 2 hour motorway drive yesterday could I have a faulty sender?
 
How cold was it Dan?

travelling around -3° to -7° normally here,takes 7 miles to get one line to left of the central 90.

Glad I never fitted the under economy stuff the frozen snow would have just ripped it all off again :cool:
 
Thats me driving with the Eco button turned on.
maybe I should block the radiator up with some cardboard old school style:p
 
Mpg

Hi Guys just brought a tdi 75 and am only getting 50 to 56 on a motor way run at 70! Is this about right as I would have thought that I would get around 60+
 
Too many factors to say for sue.

How long are the motorway journeys?
Do you read the traffic well?
How smooth are you on the brake and accelerator?
Is that exactly 70mph or a 'little' bit more at times ;)

I get 60-65mpg at 70mph and 65-70mpg at 60mph.
My journeys are typically 150 miles long and at off-peak hours.
 
Mine is pretty poor at the moment but the journeys are too short for it to get up to temp (even with the webasto running), but then as this runs on diesel its also drinking the stuff as well

Dan did you have your air-con on as this would put your webasto on wich would get you up to temp and then turn it off once up to temp

Phil
 
i think mine might be drinking a bit to much also. read thAt v power deisel might help so put that in £30 worth ie full tank as i had some fuel already in there @1.16 per litre running a 2002 75bhp se tdi and it only gave me 170 miles until it reached the red this is driving short journeys in the morning and afternoon ie droping kids to school the going to pick them up, cold starts ,car get to temp after about 15 mins into journey ,is this normal or should i be checking for faults ?
i have just had the car serviced at the dealer coulpe of weeks ago ,keep on thinking the dealer might have messed somthing up :( it used to give a bit more mpg in the summer .or am i being paraniod and could be just the weather ?
any help would be great
jai
 
My consumption has increased by @ 10% in the last few weeks which in comparison with recent winters is unusual but then again its unusual to have a normal winter. We are too used to the spell of mild winters which are probably a thing of the past.
 
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