How to clean fuel injectors without removing them?

Updated Aug 18, 2023 | Same topic: Handy Maintenance Tips

Cleaning fuel injectors sound complicated, but you can actually do it at home 

A fuel injector is a device that sprays fuel into a car’s engine. In modern vehicles, these are handled by electronically controlled valves, which in turn are controlled by the car’s engine control unit. The said valves can open and close several times in a second, adjusting the amount of fuel depending on several variables.

As you might have guessed, fuel injectors work a lot. So, in time, they can get dirty. There’s also the fact that the fuel in the Philippines, whether it be gasoline or diesel, isn’t exactly the cleanest.

How to Clean Fuel Injectors in Your Car (Without Removal)

Early signs of a dirty fuel injector include rough engine performance, bad fuel economy, and throttling problems. You might even fail your emissions testing.

So how does one clean the fuel injectors? Well, typically, this process is performed by a certified mechanic. There are, however, some ways on how to clean fuel injectors at home, without removing them.

A picture of a damaged piston head

If you don't clean dirty fuel injectors, they will in turn cause something like this eventually

>>> Related: 4 things you need to know about engine fuel injection

How to clean fuel injectors without removing them?

For most mechanics, fuel injector cleaning will involve removing the said injectors and working on them on top of a bench. Those who prefer this method say that it can provide a more thorough cleanse.

However, not all of us have the time, skill, and tools to remove the fuel injectors. So, most will turn to a method that doesn’t involve removing the part in question. And yes, this fuel injector cleaning method can be done at home.

For this, you’ll need to locate your fuel injectors first. If you’re unfamiliar with your engine layout, consult your car’s manual.

A picture of a car's fuel injectors

We suggest taking time to get to know your car better if you haven't already 

Then you’ll need a fuel injector kit. These products will typically include the fuel injector cleaning solution, which is usually made out of polyetheramine (PEA). PEA in liquid form can dissolve carbon deposits that collect inside a well-used fuel injector.

Most kits will offer a way to introduce the PEA into the fuel injectors themselves. Usually, this comes in the form of a pump. Some can be pumped by hand operation, but other more premium kits need pressurized air to work.

>>> Related: 5 signs of a bad fuel pump relay: How to clean & Replacement cost

A picture of a fuel injector cleaning cool

A fuel injector cleaning tool that pumps cleaning fluid into the injectors

In general, though, these “pumps” come with a tube that you have to attach to the fuel injector rail via a port. Before that though, make sure to detach the fuel injectors from the fuel pump. Also, you can remove the fuel pump fuse. Just to make sure, double-check the instruction manual that came with the fuel injector cleaning kit.

With the fuel line detached, you can then activate the pump which will then blow the cleaning fluid into the injector.

Next, turn on the engine with the fuel pump deactivated. The engine will burn the cleaning fluid, and the engine eventually shuts down.

Reattach the fuel injectors to the fuel pump, re-install the fuel pump fuse, and go for a test drive.

>>> Related: 5 common signs show your fuel injector is failing

How much does it cost to clean fuel injectors?

A fuel injector kit in the Philippines will typically cost somewhere around Php 400 to Php 1,500 and above. The price depends on the brand, and more complex but arguably more thorough will cost you more.

A picture of a can of fuel injector cleaning fluid

A can of fuel injector cleaning fluid from Liqui Moly

For the fuel injector cleaning fluid, this will cost you around Php 256 to Php 1,650 on Lazada PH. Again, this depends on the brand. We recommend using injector cleaning fluids from Liqui Moly, MAG, STP, and Chevron. Note that there are also OEM injector cleaners like the ones from Toyota.

How to keep fuel injectors clean?

Here’s a list of several ways on how to keep your fuel injectors clean:

  1. Keep up with your car’s regular oil changes.
  2. Replace the oil and fuel filters regularly.
  3. Consider using fuel additives that are designed to keep fuel injectors free of carbon deposits.
  4. It might not work all the time, but also consider periodically wiping your engine bay clean too.

For more useful car maintenance tips and the latest car news, keep it here on

How to clean fuel injectors without removing them: FAQs

1. Where are a car’s fuel injectors located? 

Answer: A car’s fuel injector is located in the intake manifold.

2. How many fuel injectors do a car have?

Answer: A car typically has one fuel injector per cylinder. So, if your car uses an inline-4 engine, it will have four injectors.

3. For how long does a car’s fuel injectors last?

Answer: The longevity of a car’s fuel injectors will depend on how often you change your fuel filters. Usually, though, it will last between 80,000 km to 160,000 km.

4. Where can I buy fuel injector cleaning kits?

Answer: Fuel injector cleaning kits are available from most automotive supply shops. You can also purchase one from any of the local e-commerce sites.

5. Can all of my car’s injectors go bad at the same time?

Answer: All of a car’s fuel injectors can go bad at the same time, although this is a very rare occurrence.

Cesar G.B. Miguel

Cesar G.B. Miguel


Cesar Guiderone B. Miguel was born and raised in Iligan City, Lanao Del Norte. He graduated in 2010 with a Bachelor of Arts in English degree from Mindanao State University - Iligan Institute of Technology. He previously worked as a freelance writer for various websites, as a member of the Iligan City Disaster Risk Reduction Management's training staff, and as a medical sales representative.


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