Zusammenhang Außentemperatur und Verbrauch | Posts 16+

Hi,

How significant might the temperature influence on a tire's rolling resistance be? When a tire is cold and hard, it likely requires significantly more energy to roll. When it's warm, the material is so elastic that it can be easily 'molded' into any shape. When it's cold, there is more friction, which warms the tire, but not as much as when the surrounding environment is warm.
A second factor could be the air density, but this time referring to the displacement work of the body.
Both factors may add up to the excess consumption.

Greetings.

Eike.

ulf wrote:

... -> The warmer it is, the easier the Polo rolls... and that's quite noticeable. The differences seem bigger to me than they were with my old Golf 3.

I've observed that too.
Crucially, on my main route (30km one way), the fuel consumption during the first 10km is the most important factor. And it makes a significant difference whether it starts at +5°C or 5°C. Today, the fuel consumption was approximately 4.5 liters per 100 kilometers.
These differences can also occur within a single tank of fuel. In that case, I would generally suspect lubricants and possibly the rolling resistance of the tires.

How big was the hole in the liquid cooling system?


'That's a very good question. However, it was making a terrible whistling noise, and the intercooler was covered with a thick layer of oil before it was cleaned (the workshop cleaned it before the intercooler was replaced). Now, the only thing that's still whistling is the turbocharger, and it's quite loud. What I couldn't detect before the repair was a large hole. However, it's not surprising, as the engine needed time to adjust to the different air conditions after the repair, so it wasn't pulling properly.' Now it's running really well. Next, I'm going to work on the exhaust system, because it's vibrating at idle (I have to raise the idle speed anyway, and with the current 800 RPM and occasional sputtering, it's not going to get any better), and also around 1,500 - 1,700 RPM.

Best regards, WarLord.

joegolf wrote:

Crucially, on my main route (30km one way), the fuel consumption during the first 10km is the most important factor. And it makes a significant difference whether it starts at +5°C or 5°C. Today, the fuel consumption was approximately 4.5 liters per 100 kilometers. These differences can also occur within a single tank of fuel. In that case, I would generally point to lubricants, and possibly to the rolling resistance of the tires.

I suspect so too. There isn't much difference between summer and winter during my vacation trips. The 16 km commute to work is challenging, but cycling around town is not.

Hello,

"In our Galaxy AFN, the diesel auxiliary heater makes a difference of about 0.5 liters of fuel consumption in the winter. Is there a glow plug auxiliary heating system installed in passenger cars as well?" Because it's electric, the efficiency (around 50% for the heater) and the mechanical power from the motor are quite poor compared to a real diesel engine for preheating.

Sincerely,
Christian

chris11 wrote:

Hello, "In our Galaxy AFN, the diesel auxiliary heater makes a difference of about 0.5 liters of fuel consumption in the winter. Is there a glow plug auxiliary heating system installed in passenger cars as well?" Because it's electric, the efficiency (around 50% for the heater) and the mechanical power from the motor are quite poor compared to a real diesel engine for preheating. Sincerely, Christian

The efficiency is certainly poor. However, the electric auxiliary heaters (located directly before the heat exchanger) only have an estimated power consumption of 400W, while the diesel auxiliary heater has a minimum power output of 4kW at full load.