A Guide to Fuel Injector Cleaning – Methods and Precautions

The purpose of fuel injector cleaning is to remove the buildup of fuel varnish deposits and contaminants that clog injectors and affect their operation. They need periodic cleaning for optimal operation. Experts recommend fuel injector cleaning every 25,000 to 30,000 miles or once a year.

Fuel injector cleaning not only improves functionality but also helps restore and improve engine’s performance, reduce emissions and improve fuel economy.

One good thing in fuel injector cleaning is you can do it all by yourself, without the help of an auto mechanic. However, if the injector is badly clogged, you may need to take his help. Let’s take a look at the different methods used in the cleaning.

Method#1: Using fuel injector cleaning kits
Fuel injector cleaning kits are available at any auto supply store. Before connecting the kit, locate the fuel injector and take measures to prevent fuel entering the injectors. You can do this either by using tubing to bypass the fuel injector so that the fuel returns to the tank or by removing the fuel pump and blocking the fuel return line. Once it is done, disconnect the fuel pressure regulator.

Now, connect the cleaning kit to the fuel input port and remove fuel cap of the tank to release any pressure in the tank that may built up by the kit. Open the cleaning kit’s valve till its pressure value matches with the injection pressure value (you can find injection pressure value of your car’s engine from the manual).

Once the cleaning kit reaches the required pressure value, start the engine so that the cleaning solvent passes from the kit through the injector and removes the dirt and debris that clogged the fuel injector. This will take a few minutes. Once it is done, switch off the engine, remove the kit and reconnect the fuel lines, fuel pump and fuel pressure regulator. With this, the cleaning job is done. You can notice significant difference in your engine’s performance after the clean-up.

Method#2: Adding cleaner additives to the fuel
Adding cleaner additives, also called as detergents or deposit-control additives, to the fuel helps to control the dirt and debris accumulation in the fuel tank. These additives help reduce the volatility of lighter components of the fuel. Though, the fuel from gas stations do contain certain additives, some suppliers may not add the required amount of detergents; some even use use low cost, less effective alternatives. So, you need to add additional additives to fuel.

One of the commonly used best additives is polyetheramine (PEA). Though it is a bit expensive compared to others, it is proved to be effective in keeping the injectors, valves and combustion chamber clean and it does not require any additional fluidizers.

Method#3: Manual cleaning
On-car cleaning may not be that effective for a badly clogged injector because it cannot pass the cleaning solvent during the cleaning cycle. So, when on-car cleaning doesn’t work you can for off-car cleaning, which involves removing the injector from the vehicle and cleaning it. However, this
has to be done at service center.

Off-car cleaning requires special equipment and takes more time compared to on-car cleaning. However, this is more effective as it cleans each part of injector thoroughly. Moreover, it also allows flow-testing that checks the spray pattern and volume of the injectors to confirm that they are cleaned properly.

Precautions
• Make sure to disconnect pressurized fuel connection
• Ensure there are no fuel leaks or high pressure solvents in the engine while it is operating. These solvents are highly flammable.
• Wear safety goggles for eye protection
• Close all open sources of ignitions such as sparking plugs
• Avoid contact with cleaning solvent
• Use only the cleaning kits specific to fuel injector cleaning. Don’t use other cleaners like carburetor cleaner, brake cleaner, etc.
• Don’t overuse fuel additives as they may eventually damage expensive catalytic converters

These are the popular methods used for fuel injector cleaning. If you experience clogged injectors frequently, it is better to replace them with good quality injectors that provide optimal performance for longer time.