What colors was the 2018 Beetle offered in?

Diesel #2 is a specific type of diesel fuel; not all diesel fuels are equivalent to Diesel #2. Diesel #2 typically refers to ultra-low sulfur diesel without additives, whose hydrocarbon properties meet the requirements of relevant standard tests. It has good combustibility, high energy density, and good fluidity at room temperature, making it suitable for diesel engines in heavy-duty vehicles, industrial equipment, and generator sets. Due to its low sulfur content, this type of diesel helps reduce engine wear and exhaust emissions. It is one of the common types of diesel fuel locally and is widely used in diesel-powered equipment in road transportation, agriculture, construction, and other fields.

Fuel oil #2 is a combustible liquid. Fuel oil (also known as heavy oil or residual oil) is a dark brown, viscous combustible liquid, mainly composed of hydrocarbons, with a small amount of sulfur and trace inorganic compounds. The key indicator for determining whether a substance is flammable or combustible is the flash point: substances with a flash point below 45°C are flammable, while those above 45°C are combustible. Fuel oil has a relatively high flash point, so it is classified as a combustible liquid. It can burn under specific conditions (such as high-temperature environments, contact with ignition sources, etc.), but it is not as easily ignited as flammable substances. It has high viscosity and contains a large amount of non-hydrocarbon compounds, gums, and asphaltenes. It was once used as fuel for large steam turbine boilers and medium-to-large ship engines, and now it can also be used as startup and ignition fuel for large coal-fired boilers.

#2 fuel oil and kerosene are both petroleum-derived distillates but differ in key aspects relevant to their uses in local contexts. First, their distillation ranges: kerosene boils at 150–275°C, making it a lighter fraction, while #2 fuel oil (a heavier distillate) has a higher boiling range of 200–350°C, resulting in thicker viscosity and slower flow at room temperature. In Malaysia, kerosene is used for specific purposes like aviation fuel (jet A-1 for aircraft) and, in some rural areas, traditional lamps or small cooking stoves, though its domestic use has declined with modern energy access. On the other hand, #2 fuel oil is primarily an industrial fuel, powering boilers in factories, heavy machinery, and backup generators due to its higher energy density and stability at elevated temperatures. Their flash points also differ: kerosene has a flash point around 38°C, suitable for safe storage in domestic or aviation settings, while #2 fuel oil’s higher flash point (around 52°C or more) enhances safety for industrial storage and use. Sulfur content regulations apply to both; aviation kerosene adheres to strict low-sulfur standards, while industrial-grade #2 fuel oil typically has higher sulfur levels aligned with local industrial emission guidelines. These differences ensure each fuel is optimized for its intended applications in the country’s energy landscape.

The practice of adding two-stroke engine oil to diesel fuel is mainly applicable to two-stroke diesel engines. Due to their compact structure and lack of an independent lubrication system, these engines require two-stroke engine oil to be mixed with diesel fuel in a specific ratio. This allows the oil to lubricate internal moving parts such as pistons and crankshafts while participating in combustion, preventing wear under high-temperature and high-speed operation, as well as assisting in cooling, sealing, and cleaning the engine interior. However, for four-stroke diesel engines, adding two-stroke engine oil to diesel fuel is not recommended. Since they have an independent circulating lubrication system where the oil does not participate in combustion, adding two-stroke oil can easily cause carbon deposits, clog fuel injectors or high-pressure fuel rails, and affect engine performance. It should be noted that the use of two-stroke engine oil must strictly follow the manufacturer's recommended ratio to ensure the normal operation of the engine and extend its service life.

Fuel Oil No. 2 (locally often referring to diesel for specific purposes) appears red due to the addition of compliant red dye, primarily intended to distinguish its usage and tax attributes. Locally, red diesel generally falls into the category of tax-exempt or subsidized fuel, designated exclusively for agricultural machinery, fishing vessels, industrial generators, off-road engineering vehicles, etc. In contrast, diesel used by ordinary road vehicles is typically light yellow and subject to full taxation. The addition of dye enables law enforcement agencies to easily identify and monitor the fuel, preventing tax-exempt fuel from being illegally used in road vehicles to evade taxes. This dye is compositionally safe and does not negatively impact the fuel's combustion efficiency or equipment performance. Furthermore, color-coded fuel labeling is a common practice in the local fuel management system. In addition to red diesel, other colors are used to distinguish fuels of different grades or purposes, aiding users and regulators in quick identification. This ensures compliance with relevant regulatory requirements, maintains a fair taxation system, and upholds standardized fuel market practices.