Winter MPG?

[goatboy]

I know this has sort of been covered before but I was hoping for a little confirmation...

I've got a tdi170 and my fuel economy seems to have dropped a good perecntage in the last few months.
When I first got the car (in the summer) I would quite often manage 60+mpg on my 30 mile commute, now I am stuggling to get 50+mpg in similar conditions except the weather.

As an example I drove up to Nottingham from Hertfordshire for NYE, I had about 5-10 minutes driving round town and then straight onto the motorway, I had the cruise set at 71mph and there was also a long section (10+ miles) of 50mph roadworks. By the time I got to Nottingham (about 1hour 40 journey) the car was only showing 52mpg.

Now I was expecting mpg to get lower in winter but I would have not expected it to be that much lower. Can anybody confirm if they have similar expereinces?

I was soooo pleased with getting about book figures when I first got the car and now I feel a bit cheated...

Thanks

[a4gee]

Colder weather means you`ll always get a lower reading.

[goatboy]

sure, but I was expecting 2-3 mpg difference not 10mpg. thats 20%!

[nuroc]

Mine's dropped 10mpg as well over the last month or so, with no change to my driving style and over the same routes.

[sharkey964]

I did a run from here in the SW of france to Dover,week before xmas,@ an average of 5.8l/100km.
I think that works out at around 40mpg.
A distance of 1800km=1118 miles.

[goatboy]

Mine's dropped 10mpg as well over the last month or so, with no change to my driving style and over the same routes.

Sounds like its not just me then. It has actually been marginally better the last week because its been a bit warmer. I'm suprised it is soooo sensitive to temperature.

(wouldn't mind so much if it made it feel faster too)

[jimma1983]

Mine has dropped from an average of 47 to 40 on the last tank.

[coullstar]

Aye these new Tdi's dont like the cold it seems. Im still averaging 32mpg in my mapped TFSI and had 40mpg on the clock the other day.

[nuroc]

This morning, with an outside temperature of -4C, on my 10 mile trip to my first appointment my 140 TDI did... 26.8mpg!

This was driving carefully (first time I've driven my Scirocco on ice) and not exceeding 50mph. It really doesn't like the cold does it?

[Cuprabob]

I've just noticed a drop of around 2-3mpg in mine

[yaroc]

I think there are a number of factors at play here
1.The colder it is the longer it takes for the engine to get to its optimum working temperature, I do a 22 mile commute each day and it takes 15-20 minutes before the oil temp gets into the range of 95-98 C. and don’t forget we want the heater on full drawing more heat from the engine.
2. We are now using a winter type diesel mix, oil companies change the mix slightly to make sure the viscosity remains the same in cold weather.
3. If your car decides to do a DPF regen during your journey you can expect your fuel consumption to suffer

[maisbitt]

I've only noticed a 5% dip in mine, although for the past few days i've been taking it very easy due to the icy roads and penny pinching lack of grit on the local roads.

Colder, less humid air makes for significantly less combustion expansion.

Having the heater on saps the engine's heat when it's trying to warm up, making it take twice as long to reach operating temperature in my experience.

Higher drain on the battery in the winter with extensive use of lights, the battery having a lower capacity in the cold and greater reliance on glow plugs to start up, so the battery makes the alternator work overtime.

Higher drag from the tyres if you haven't adjusted your tyre pressures in the cold (colder temp = lower pressure for same fixed volume of air).

Expect at least 10% dip in fuel economy in the winter unless you adjust your driving style due to risk of black ice etc.

[Trickytree1984]

Only had my car 1 month. Same drive every day with similar driving. Last week when the temps were 10c I was getting 60 to 65 mpg. This week with the temps around 0c to -5c I have been getting around 50 to 55 mpg.

Firstly the cr will use more fuel to get warm. Secondly I have had full windscreen clear, rear window, heated mirrors and heated seats all on.. The heaters will be working harder as well.. Al perfectly normal.

Also in the bluemotion, the start stop does not function in sub zero to my experience. I think it's quite intelligent and calculates the external temp is too low compared to the target temps. It never works when I have heated seats on!

[bleedsoff]

I usually get about 8mpg in the cold weather. It takes about half my commute to get the engine up to temp while in the summer prob be warmed up in a 5 minutes. I have a 40 minute commute.

[maisbitt]

I usually get about 8mpg in the cold weather. It takes about half my commute to get the engine up to temp while in the summer prob be warmed up in a 5 minutes. I have a 40 minute commute.

Bleedsoff - that must be a mistake. Do you mean you get an 8mpg drop off in the winter as opposed to actually getting 8mpg on your 40 mile commute (or is that a 2 mile commute on a 40 minute crawl?)?

[bleedsoff]

I usually get about 8mpg in the cold weather. It takes about half my commute to get the engine up to temp while in the summer prob be warmed up in a 5 minutes. I have a 40 minute commute.

Bleedsoff - that must be a mistake. Do you mean you get an 8mpg drop off in the winter as opposed to actually getting 8mpg on your 40 mile commute (or is that a 2 mile commute on a 40 minute crawl?)?

LOL, yes suppose to be 8MPG less!

[goatboy]

Good to see everyone has a similar experience and its not a fault on my car.

It all makes sense why mpg would be lower, its just suprising how sensitive it is.

Roll on summer!

[gibbsy]

I managed to prise my very heavy right footed wife out of the drivers seat to go for a 34 miles trip, 30 of which were dual carriageway and motorway. I was careful and kept to 70ish and returned 62.4 mpg. Once the trip showed a figure over 60 I kept prodding her the pointing at the dash. She drove home..............51.5 mpg. However she did thank me for saving some motion lotion so that she could have the fun on the way home.