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How to Clean your Gas and Diesel Fuel Injectors

Your engine’s fuel injectors deliver fuel into the combustion chamber in synch with the motion of the pistons. But, the diameter of an injector orifice is tiny, even smaller than the diameter of human hair. Therefore, it’s common for carbonaceous deposits on injectors to impede fuel flow and starve your engine of fuel, dramatically reducing performance. The good news, your injectors can be cleaned to restore horsepower and torque.
So, you want to know how to clean your fuel injectors?

Pay the pros

One method is to take your vehicle to a mechanic and have them clean your injectors for you. However, as you might guess, this is not the cheapest approach, and it comes with the hassle of scheduling service and living without your vehicle while it’s at the shop.

Do it yourself

You could take on the project yourself. You can easily find instructions online on how to remove fuel injectors from the engine, clean them and reinstall them. The process can be done with the right tools and knowledge, but there is an easier way.

Use a fuel additive

Using the right fuel additive to clean fuel injectors is a simple approach that’s also inexpensive and just as effective. However, as this post explains, this technique requires a fuel additive with enough strength to get the job done.

AMSOIL P.i.® Performance Improver

AMSOIL P.i. Performance Improver gasoline additive contains concentrated detergents that aggressively clean stubborn, power-robbing deposits from injectors, valves and the combustion chamber. It’s effective in port and direct-injection systems and cleans the entire fuel system in one tank.

AMSOIL P.i. restores GDI fuel injectors up to a 100% flow rate¹ and restores up to 14% horsepower.² P.i. also fights intake valve and combustion chamber deposits to help restore power, control knock and reduce the need for higher-octane fuels. Use AMSOIL P.i. every 4,000 miles to thoroughly clean the injectors, valves and combustion chamber.

AMSOIL P.i. increases horsepower.

AMSOIL Upper Cylinder Lubricant

Your engine’s top-end is sparsely lubricated and prone to the development of deposits and corrosion, an issue compounded by ethanol in fuel. While P.i. Performance Improver is designed to attack and remove stubborn deposits, Upper Cylinder Lubricant helps preserve injector and combustion-chamber cleanliness between P.i. treatments. Use AMSOIL Upper Cylinder Lubricant in every tank of fuel to help maintain peak performance.

AMSOIL Upper Cylinder Lubricant also delivers 18% more lubricity than Lucas* and 20% more than Sea Foam* for better retention of horsepower and fuel economy

Graph shows that AMSOIL Upper Cylinder Lubricant delivers 18% more lubricity than Lucas* and 20% more than Sea Foam* for better retention of horsepower and fuel economy.

AMSOIL Diesel Injector Clean

AMSOIL Diesel Injector Clean will take care of your dirty diesel engines injectors. Its concentrated formula uses unique chemistry to target and eliminate carbonaceous deposits and help maximize power. Use AMSOIL Diesel Injector Clean in every tank of fuel to help maintain maximum performance.

AMSOIL Diesel Injector Clean

AMSOIL Diesel 4-IN-1

AMSOIL Diesel 4-IN-1 provides better cold flow, increases cetane, fights fuel-system corrosion and cleans injectors to help restore lost power and torque and reduce smoke and emissions. Use it regularly to increase diesel fuel lubricity for improved wear protection.4 Maintain your diesel engine by adding AMSOIL Diesel 4-IN-1 to each tank to help clean dirty injectors and provide exceptional all-season protection and performance.

How to clean fuel injectors

You don’t have to take your vehicle to a mechanic to fix clogged injectors or live with the loss of horsepower and performance. High-quality AMSOIL fuel additives can help clean clogged fuel injectors and keep them clean with minimal cost and effort.

1ASTM D5598(M) – 2013 Buick Regal test vehicle.

2Based on third-party testing in a 2016 Chevrolet* Silverado* 1500, 5.3L V-8 GDI with 100,616 miles, using one tank treated with AMSOIL P.i. Actual results may vary.

3Based on independent testing of AMSOIL Upper Cylinder Lubricant, Lucas Upper Cylinder Lubricant and Sea Foam Motor Treatment obtained on 02/13/2019 using the ASTM D6079 modified for use with gasoline.

4Fuels tested in 2017.

by Brad Nelson

Brad Nelson is a staff writer for AMSOIL. Outside of work he enjoys family adventures, wilderness exploration and riding/wrenching on vintage metric motorcycles.

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