Why higher fuel consumption at lower outdoor temperatures?

Hi everyone.

I drive a Golf 5 BLS with a DPF.

I've noticed for some time that the energy consumption is generally higher at lower AT levels compared to warmer temperatures.

I drive the same route every day, approximately 100km to work.

To rule out the cold start issue, I reset the BC (Boost Control) only after driving for 30km, when the engine was already fully warmed up, and at the same location.

Example: at 15°C -> Consumption 5.5L/100km
at -5°C -> Consumption 6.2 L/100km

I have tested it at least 30 times and have found that the consumption is clearly higher at low temperatures, almost inversely proportional to the temperature.

But why?

Electric appliances were limited to lighting and radio, nothing else, no additional heating etc...

I have been driving my 1.4 HDI, assuming normal operating temperature ("warm"), which resulted in lower fuel consumption. The minimum fuel consumption for my vehicle is within a range of -5 to +8 degrees Celsius outside temperature. Below this, I experience difficulty in achieving and maintaining the "warm" operating temperature, given my driving profile. The fuel consumption increases in the range of approximately 5 degrees, but only within a demonstrable range (+0.5 l). It is important to note that, although the 1.4 HDI engine is turbocharged, it does not have an intercooler.

You Lucky One,

My BLS is still costing me a fortune. I can't get below 6.2L/100, even with very economical driving. Always stick to country roads, rarely exceeding 100 km/h.

Consumable levels below 6L are only achievable when the temperature is significantly above 10°C.

Could this possibly be related to the diesel temperature?
As soon as the accelerator pedal is touched, at least 5L are displayed in the current consumption indicator.
LMM and the thermostat were already replaced based on suspicion, even though no defect was apparent.

That's not worth it anymore.

Quote:

But why?

That has many reasons -- > increased friction from wheel bearings, drive shafts, and gearboxes.
At temperatures below the freezing point, under normal conditions, none of these components will reach temperatures like 15° +, even after 30km.
Evt. the engine mapping for these temperatures/air temperatures is not 100% optimal/optimized.

In conclusion, this ultimately leads to increased consumption.

You, the lucky one,

My BLS is still making me lose my hair. Even with the most economical driving style, I won't get below 6.2L/100.


What's wrong with real 6-6.5 liter engines?

Autoservice wrote:

But why? Quote: That has many reasons -- > increased friction from wheel bearings, drive shafts, and gearboxes.

Higher air resistance also comes into play.

Hello Klaus

What values do the temperature sensors provide?
hg
Herbert

mullemaus wrote:

What's wrong with a real 6-6.5 liter engine? :wink:Maybe the fact that I can also drive my old T4(!) with a TDI engine?

Well, the green sticker is demanding its due...

Quote:

Example at 15°C -> Consumption 5.5L/100km at -5°C -> consumption 6.2 L/100km

Average fuel consumption for this model is approximately 5.74 liters/100km, so everything is within the acceptable range!

Don't forget the higher rolling resistance of winter tires.
I never thought it would make such a big difference.

However, last summer I drove my A2 3L the same route many times, and according to the on-board computer, the fuel consumption was 3.5L.
After switching to winter tires all at once, 4.1 liters

And that's usually how much he needs in the winter, even if I reset the onboard computer after it reaches the 90-degree engine temperature.
The tread depth was identical at 6mm for both tires.

Oh, in terms of percentage, your winter tires are consuming significantly more! Also, one should not forget that, depending on driving habits and vehicle usage, the proportion of driving times and distances that are driven below the operating temperature in winter is higher. Vehicles that already take a long time to reach their optimal operating temperature are now operating in fuel-efficient ranges for significantly longer in winter, and some no longer reach their "optimal operating temperature" at all.

... and BLS prefers a very short gear ratio, so that once he's moved on, he also likes to drink.

In France (140 km/h on the highway), our car also achieved 6.1 liters per 100 kilometers. On country roads, it is significantly more fuel-efficient.

m;

Does he really need the short gear?

In my opinion, NO.

At least, if there's one more gear available, it has enough torque from below.
One can easily drive it (with some feeling) at 2-4-6.
The Passat would probably mess it up in the second.

I am referring to this BLS:
[code]Address 01: Motor Label file: User\03G-906-021-BLS.lbl
Part Number: SW; 03G 906 021 QJ HW; 03G 906 021 AB
Part Number: R4 1.9L EDC G000SG 1984
Revision: --H07--- Serial Number: VWXBZ0G0722272
Encoding: 0000072
Operating number: WSC 39799 133 20514

Here, specifically (at the bottom), it is noticeably more compact:
[code]Address 01: Motor Label file: User\03G-906-021-BLS.lbl
Part Number: SW; 03G 906 056 HW; 03G 906 021 AB
Part Number: R4 1.9L EDC G000SG 2832
Revision: --H11--- Serial Number: VWX7Z0I53N40A5
Encoding: 0000072
Operating Number: WSC 01324 020 00200

But that now has nothing more to do with the initial question "increased consumption at low temperatures".

Please stay on the topic of .

Furthermore, the BLS is actually quite frugal.
and that's exactly why it doesn't like getting warm when it's cold.

When driving in city/short-distance traffic, he also sometimes prefers to use two-digit numbers, especially if you're only driving a short distance.

At 6.1, I wouldn't be too inclined to take drastic action.
The last bit of fuel is then squeezed out with the appropriate driving style

We are also 21% above prospectus - which is due to the scope of use:
http://www.spritmonitor.de/de/detailansicht/354700.html

m;

EDIT:

Um:

Quote:

Electrical appliances were limited to lighting and a radio, nothing else, no additional heating etc...

Where do you know that the heating element in the air conditioner was not on?