How to Clean Fuel Injectors

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Fuel injectors (Photo: @FreedomTumZ via Twenty20)
Fuel injectors spray atomized fuel (or gasoline) into the engine’s combustion chamber.
When your fuel injectors aren’t regularly cleaned, the buildup of dirt and grime can take a toll on your vehicle. Clogged fuel injectors can cause problems that impact your car’s performance like engine misfires, poor idling, and even breakdowns.
It goes without saying, it’s better to prevent these issues by maintaining your fuel injectors. In fact, cleaning your fuel injectors might be easier than you think! Here’s what you need to know.

Gather materials and prepare your work area

Before you start working, make sure that you have a flat work area with adequate ventilation. An open garage or a driveway will do the trick. To clean your fuel injectors, you’ll need the following items:
  • Wrench set (both socket and regular)
  • Fuel injector cleaning kit
  • Air compressor
  • Fuel system cleaner
  • New injector O rings (if needed)
Once you have all of the required tools, you can begin the fuel injector cleaning process. Familiarize yourself with the instructions for the fuel injector cleaning kit before beginning.

1. Fill the fuel Injector canister

Start by removing the cap on the fuel injector canister and filling it with the recommended cleaning solution. The canister is the tool that comes with your cleaning kit that allows you to easily run fuel injector cleaners through your fuel injectors. Hang the canister in a convenient location under the hood.

2. Locate the fuel rail test port

Next, locate the fuel rail test port. The location of this test port depends on the make and model of your vehicle. If needed, consult your owner’s manual to determine its location. Once you’ve found it, connect the hose from the fuel injector canister to the test port.

3. Disconnect fuel pump relay

Find the fuel pump relay and disconnect it as directed by your cleaning kit instructions. The fuel pump relay is in the fuse box of your vehicle.

4. Attach air supply

Next, attach the air supply to the fuel injector canister air port. Adjust the regulated system pressure, as displayed on the canister meter, to the instructed level. This is usually slightly lower than the pressure used to provide fuel to the fuel injectors.

5. Start your car

Remove the fuel cap and start your car. Removing the cap prevents the buildup of pressure, which can cause combustion to occur in the combustion chamber. Allow the solution to flow out of the fuel injector canister and through the fuel rail. This process usually takes between five to ten minutes.

6. Disconnect air supply

After the canister is empty, release the line pressure and disconnect the air supply. Remove the hose from the fuel rail test port. Next, remove the canister from underneath the hood.
You should clean your fuel injectors once a year to ensure they stay clean. If you notice abnormal noise after performing a fuel injector cleaning, take your vehicle to a professional auto mechanic to get it checked out.