The reality behind diesel engines: 7 myths we need to debunk

Diesel engines have been the subject of debate for years, victims of numerous myths that have contributed to their negative image in the market. As diesel vehicle sales decline, particularly in regions like Spain where they barely represent 10% of the market, it is crucial to unravel the misconceptions surrounding these propulsion systems. Paradoxically, in a world where electric options are gaining prominence, diesel engines are more advanced than they are perceived. This text aims to clarify and debunk the seven most common myths about diesel cars, revealing the true efficiency, cleanliness, and durability that these engines can offer.

The diesel engine sector has been the subject of numerous myths that have circulated for years, affecting public perception and, consequently, their sales. Today, with a declining market share, it is vital to address these myths one by one to better understand the reality behind diesel engines. This article seeks to demystify seven common and incorrect beliefs about diesel vehicles, from their maintenance to their efficiency, and provide a clearer and more accurate picture of their operation.

It is more expensive to maintain

There is a widespread perception that diesel cars are more costly to maintain. It is true that some spare parts may be more expensive, but on the other hand, the longevity of diesel engines is superior, allowing for more kilometers driven before reaching the end of their useful life. Furthermore, the maintenance of these engines can be performed at longer intervals, which means fewer visits to the workshop and significant savings in the long run.

They are noisy and dirty

Previously, diesel engines were synonymous with noise and pollution. However, technology has advanced significantly. Now, these engines are much cleaner thanks to innovations such as the particle filter and the selective catalytic reduction SCR system, which have considerably reduced harmful particulate emissions.

They have less power

Another recurring myth is that diesel engines have less power. Although in the past they could be less powerful due to a lack of turbochargers, nowadays, diesel engines offer high power levels, comparable to many gasoline engines of similar displacement, and have the advantage of providing greater torque at lower RPMs.

They have starting difficulties in winter

While it is true that in extreme climates a diesel engine may take longer to start, the current difference with gasoline engines is minimal. Modern technology has improved this aspect with electronic fuel injection systems and heaters like glow plugs, facilitating cold starting.

Vegetable oil as fuel?

There is a belief that vegetable oil can be used as fuel in diesel engines. While certain biodiesels include vegetable oils to reduce emissions, pouring vegetable oil into the tank can drastically shorten the engine’s lifespan. It is important to continue using fuels designed for these engines.

Worse performance at higher altitudes

Contrary to popular belief, diesel engines perform better at high altitudes thanks to turbochargers, which compensate for the lower oxygen density by delivering thin air to the combustion chamber. While there may be a slight reduction in power, performance remains better compared to a gasoline engine under the same conditions.

Letting a diesel engine idle is good

The myth that it is beneficial to let a diesel engine idle to warm up is false. Modern diesel engines do not require waiting before starting the vehicle, allowing for smooth driving right from the beginning.

Learn how Dacia is phasing out the diesel engine.

The future and perception of diesel engines

In the current automotive landscape, the perception of diesel engines faces significant challenges. The decline of their market share, particularly in regions like Spain, where their share could fall to 10% by 2024, reflects a shift towards more electrified options.

One of the factors contributing to this decline is the negative image that diesel engines have acquired among the public. This perception does not develop in isolation but is fed by a series of myths and misconceptions that have circulated for years.

Debunking these myths is crucial for understanding the true potential and drawbacks of diesel engines. A significant change in their design and technology over the past decades has resulted in quieter and cleaner engines, dispelling the belief that they are inherently noisy and dirty. Additionally, innovations such as turbochargers have increased their power, making them more competitive.

Another aspect that tends to be misunderstood is engine start in cold climates. Thanks to technological improvements, such as electronic fuel injection and heaters, these difficulties have been significantly reduced.

On the other hand, myths surrounding their capabilities at high altitudes and the use of vegetable oil as fuel are revealed to be falsehoods, showing that diesel engines can even operate more efficiently in low oxygen pressure scenarios.

Finally, the belief that letting the engine idle is beneficial confronts the reality that modern diesel engines do not require such practice.

Despite these misunderstandings, diesel engines still offer some advantages, such as lower fuel consumption and prolonged lifespan. However, the pressure of environmental regulations and advances in electric technology present an uncertain future for them.