When your car starts getting lower gas mileage or the engine begins to hesitate when you press the gas pedal or rough idle, it might be time to clean your fuel injectors. You can have this done at the mechanic, but you can save money doing it yourself. All you need is a fuel injector cleaning kit and a fuel line disconnect tool.

• Purchase a fuel injector cleaner kit.These are available for purchase at any auto store, or you can buy one online. Cleaning kits come with a canister of fuel injector cleaner, a gauge you use to determine the fuel pressure, and a hose that attaches to the fuel injector and fuel rail.

Most fuel injector cleaning kits can be used for any type of vehicle, but read the manual to make sure the one you pick out is a good match for yours.

Sometimes the required cleaning fluid is sold separately from the canister and other tools that come with the cleaning kit.

• Review your vehicle’s engine layout.Take a look at your vehicle’s manual to determine where the fuel injectors are located. Identify the locations of the fuel pump and its components as well.
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  Disconnect the fuel pump from the fuel injectors.Either connect the fuel return line, or insert a U tube so the gas returns to the tank while you’re cleaning the injectors. Some vehicles require you to remove fuel pump fuse or relay.

Follow the instructions in your vehicle’s manual if you aren’t sure how to disconnect the fuel pump and connect the fuel return line or insert a U tube.

• Disconnect the pressure regulator vacuum line.
• Connect the cleaning kit to the fuel pressure test port.This is attached to the fuel rail in your engine.

Your fuel injector cleaner kit will have detailed instructions on how to attach the hose and fitting to the fuel port.

Make sure the injectors have no exposure to fuel, as the cleaner is flammable.

• Remove the cap from the fuel tank.The cleaner will clean debris and grime by using a burst of pressure to inject a cleaning solvent into the fuel injectors. Opening the fuel cap will prevent excessive pressure from building up, which could cause combustion.
• Turn the vehicle on and let the engine run.Before you do this, double check to make sure that the fuel pump is turned off.

It usually takes 5 to 10 minutes for the cleaner to cycle through the injectors and get used up. Follow the instructions that came with your cleaner kit.

The engine will shut down on its own after the cleaner has been fully used.

• Reattach the fuel pump power supply and the pressure regulator vacuum hose.
• Turn the vehicle on again to make sure the fuel injectors work.Listen for any abnormal noises. Drive the vehicle a short distance to make sure it runs smoothly.If you followed the procedure correctly and notice abnormal noises, contact a professional auto mechanic.

If your vehicle is still getting bad gas mileage, hesitating when you press the gas pedal or runs rough, take it to a mechanic, as you may need to replace the fuel injectors or address a different problem.