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What causes fuel injectors to get clogged or dirty?

by LiMona 25 Dec 2023

How Can I Tell If My Fuel Injectors Are Clogged?

Acceleration Trouble

Your vehicle needs a fresh injection of gasoline every time you step on the accelerator. If the fuel injectors are clogged, your vehicle will not be getting the gas it needs to generate the power to go faster. The result is a sluggish response to your acceleration commands, including when you are stopped or when you are trying to pick up speed on surface streets or highways.


Bad Gas Mileage

Fuel injectors clogged in the open position can affect your gas mileage. Your engine is getting too much gasoline from the open fuel injectors and it will burn off the excess. This will reduce the gas mileage you get out of each tank, as will the engine working too hard if the injectors are clogged partially closed, and stressing the engine out. Your engine needs gas to start and continue to run.


Hard Engine Starts

Depending on how badly your fuel injectors are clogged, you may not be able to get your car started at all. You may get a sign that the injectors are starting to have problems if your automobile has suddenly become harder to start every time you turn the key in the ignition. A hard engine starts or a dead engine can indicate that there is no fuel or that the engine is flooded.


Why Does Fuel Injector Clogging Happen?

The fuel injector is what brings the gasoline necessary to run the car into the engine. Consequently, it should be a surprise to no one that gasoline itself is the primary reason for the injectors to get clogged. However, it isn’t entirely correct that dirt from the gasoline creates the clogs. The ingredients of the gasoline sold at the pump are a witch’s brew of hydrocarbons that are not always light matter. The heavy hydrocarbons generate greater energy but leave behind deposits in the fuel injector. The heat from the engine itself encourages the development of deposits by evaporating fuel that may be lingering in the injector tips. The deposits will build up and harden within the injectors. Detergent is added to gasoline to prevent the buildup, but everyday traffic in the city can cause the deposits to form quicker than the detergent can remove them. Sometimes what is supposed to help serves to hinder. That is the case with ethanol. While it has been touted as being great for the environment, ethanol’s ability to get rid of sludge can create deposits that end up harming the fuel injectors.


How to Unclog Clogged Fuel Injectors?

Although many products such as injection cleaning additives claim they can clean or unclog a clogged fuel injector while it is in the engine, they cannot. For any of these products to work they have to get inside the injector. Common sense predicts that if you cannot get inside something, you are not going to be able to clean it.


By adding fuel injector cleaners to the fuel, the problem will most probably be exacerbated. Why? The injector cleaner has a cleaning effect on everything it touches. All the debris loosened by the cleaner is pumped to the fuel injector set that already has a problem. This makes the problem worse because more debris is pushed into the injectors or the pathway to the injectors. To unclog a clogged fuel injector properly the filter basket must be removed. Sediment and dirt built up between the pintle shaft and injector body must be cleaned. Once it is verified that the injector is completely clean, new filter baskets can now be installed.



If you're aware of Injector problems with your car or have questions about engine replacement components, HP injection has the answers you're looking for – and the products, too!

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