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I have been asking around this question for a long time now, but I still don't have a good answer for it.
Why does it take longer for a diesel engine to warm up an interior of a car in comparison to a gasoline engine?
 

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I have been asking around this question for a long time now, but I still don't have a good answer for it.
Why does it take longer for a diesel engine to warm up an interior of a car in comparison to a gasoline engine?

Diesels don’t run as warm as gasoline engines and many drivers still remember how long it took the interiors of 1970s and 80s Mercedes and Volkswagen diesels to warm to a comfortable level. That's why the 2011 Golf TDI that I have have heated seats. And boy do they work.
 

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Cast iron block and beefier components = more mass to warm up.
Less waste heat = less heat transferred to engine coolant (engine coolant warms the cabin).
 

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Diesel engines have an higher thermal efficiency that petrol so more heat from the fuel burnt does work and isn't absorbed into the cooling system. This is mainly due to the higher compression ratio of a diesel. A petrol engine has a thermal efficiency of 25% a diesel has a thermal efficiency of 35% thats why you get more miles per gallon. Thats why for every $1 of fuel you put in a petrol you get 25 cents of power out of it and 35 cents of power from a diesel.

VW know that diesels take longer to warm up thats why they fit an auxilary heater in the heater system thats burns diesel in its own chamber to warm the inside of the car in colder countries.

Thermal Efficiency

Diesel Cycle

Diesel Engine
 

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I have been asking around this question for a long time now, but I still don't have a good answer for it.
Why does it take longer for a diesel engine to warm up an interior of a car in comparison to a gasoline engine?
I have heard, that it is because a diesel engine, is made of thicker metal.

Another theory I have, is that a gasoline engine takes more rpm than the diesel engine, which means that petrol makes more burns
 

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Another theory I have, is that a gasoline engine takes more rpm than the diesel engine, which means that petrol makes more burns
What you mean by take more RPM's? You talking about idle or cruise speed?
Either one i'm going to have to bust that theory. :) Unless you mean that a gas engine requires more fuel to burn to mantain a set rpm then a diesel? Diesel fuel dose burn cooler.
 

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I have heard, that it is because a diesel engine, is made of thicker metal.
They are slightly more robust because of the higher combustion pressures involved thats why they don't generally rev higher than a petrol.

Another theory I have, is that a gasoline engine takes more rpm than the diesel engine, which means that petrol makes more burns
I think he means that petrol engine tend to rev higher than diesel engnes and therefore more fuel is burnt.
 
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