How to Clean Fuel Injector

The fuel injectors in today’s automobile engines are among the engine's most critical components. Maintaining clean fuel injectors keeps the engine running at peak power and performance, saves gas, and cuts down on harmful exhaust emissions.
Clean fuel injectors are usually compromised by dirty fuel and fuel contaminated with water resulting in clogs and rust, respectively. You can clean fuel injectors using one of three different methods. The least effective method involves adding cleaner directly to the vehicle’s fuel tank. The wide variation in product quality and the inability to qualitatively measure effectiveness means that this method is, at best, a stop-gap measure.
The second method to clean fuel injectors is “on-car” injector cleaning. As this involves a fairly comprehensive mechanical knowledge, as well as working with pressurized, toxic and highly flammable materials, the on-car procedure to clean fuel injectors is not recommended for the faint of heart.

The last and most effective method for cleaning fuel injectors is to bring the vehicle to a mechanic with the proper knowledge and equipment for both cleaning and testing the fuel injection system. Most often, for less than $40 US Dollars per injector, the mechanic will remove the fuel injectors, clean the injectors “off-car” with an injector cleaning machine, and, using the same machine, test the injectors to ensure that they’re functioning properly. Should defects be found in the injectors themselves, the mechanic can replace the injectors. These new fuel injectors should be guaranteed, though this is a pricey alternative.
If you wish to try the on-car method to clean fuel injectors, various steps must be accomplished to ensure safe and effective results. With the engine off and no spark or open flame close by, disconnect the necessary fuel lines, making sure a container is properly placed to catch the fuel runoff from the lines. Next, either disconnect the fuel pump which may lead to an fault code in the vehicle’s computer or install a U tube to cycle fuel away from the engine and back into the tank while the cleaning process is being performed. 
Wearing eye-protection, connect a pressurized container of cleaning solvent to the injectors. Avoid skin contact with the solvent. Start the engine and allow the solvent to flow into the injectors. When solvent has been properly fed into the injectors, shut off the engine. Remove the cleaning apparatus and reattach the fuel lines and the pump. Finally, take the vehicle for a test drive to determine the effectiveness of the cleaning and, if necessary, repeat the process to completely clean fuel injectors.