Ethanol gasoline has been widely adopted abroad. Both Brazil and the United States are major countries in the production and use of ethanol gasoline.

China is also stepping up its efforts to promote ethanol gasoline. In fact, this is a positive development for both the country and its people. Not only does it enable the rational use of energy resources, but it also effectively reduces automobile exhaust emissions and helps improve our country’s ecological environment. More than a decade ago, many provinces and cities across the country had already begun using ethanol gasoline. It’s fair to say that the overall results have been quite promising.

Before switching to ethanol gasoline, it’s best to clean the fuel system of your gasoline-powered vehicle. Otherwise, the fuel supply system is likely to malfunction. At its mildest, this can result in insufficient engine power and excessive emissions. In more severe cases, the engine may stall completely and fail to start up again. This is not an exaggeration—just understand the structure of your car’s fuel system correctly, and you’ll see why.

The fuel system of a gasoline vehicle mainly includes: the fuel tank, fuel pump, fuel filter, fuel distributor, fuel pressure regulator, fuel injectors, and fuel lines. As shown in the diagram above, any blockage in any segment of the system can lead to insufficient fuel supply, thereby causing the engine to stall. It’s worth noting that in some vehicles, the fuel pump is located inside the fuel tank (as shown in the diagram above), while in others, the fuel pump is located outside the fuel tank (as shown in the diagram below).

For most vehicles, the fuel system can become contaminated due to various conditions encountered in daily use—for example, problems may arise from the gasoline typically added by vehicle owners; vehicles might be parked for long periods or driven at low speeds for extended durations; and due to busy schedules or negligence, vehicle maintenance and servicing may not be carried out promptly. Although some of these residues are very fine, they tend to accumulate over time, forming sludge deposits on the inner walls of the fuel lines. Additionally, the nozzles of fuel injectors may develop carbon buildup. During repairs, many auto repair shops usually only replace the fuel filter without cleaning the entire fuel system—a practice that falls far short of providing adequate maintenance.

Ethanol gasoline has a stronger dissolving power than conventional gasoline. When ethanol gasoline is first used in gasoline-powered vehicles, it will initially dissolve residues accumulated on the inner walls and bottom of the fuel tank. If mixed with gasoline, this can lead to poor fuel delivery; in severe cases, it may even cause the fuel pump to run dry, overheat, and eventually get damaged. The inner walls of fuel lines and other components may also have their accumulated dirt and residue dissolved by ethanol gasoline, potentially damaging parts of the fuel supply system or mixing with engine oil, resulting in injectors failing to deliver fuel or becoming clogged—and ultimately causing the engine to stop working. If these problems occur while you’re driving on the road, wouldn’t you just be stuck there?

Therefore, before using ethanol gasoline, it’s best to have the fuel system cleaned and maintained at a reputable and reliable garage.

① First, clean the fuel tank. It’s best to perform the cleaning when the fuel level in the tank is low or after some fuel has been drained. Add an appropriate amount of fuel system cleaner to the tank to dissolve sludge, deposits, and moisture inside.

Wait about 20 minutes, then open the oil tank’s drain plug to release the mixture of cleaning agent, oil, and impurities. Check whether the discharged material is dirty. If it’s dirty, repeat the cleaning process several times. If it’s excessively dirty, remove the oil tank and place it on the ground. Once cleaned, inspect it carefully. Due to severe rusting on the inner walls, some oil tanks may need to be replaced. Be sure to check and replace them promptly, and take this opportunity to address any underlying issues as well.

② Clean the fuel pump. Whether installed inside or outside the fuel tank, the fuel pump should be removed whenever possible and inspected to determine whether it needs to be replaced. Use a specialized cleaning agent to remove any sludge buildup at the inlet and outlet ports.

③ Replace the fuel filter. The fuel filter is a critically important component of the fuel system, and the cleanliness of the fuel supply system largely depends on it.

You can open the drain plug to let the impurities out and see if it’s really...