What you might be thinking about is one of these things:
* Fuel Filter Replacement: This is a crucial maintenance item. The fuel filter cleans contaminants from the fuel before it reaches the injectors. A clogged fuel filter can severely damage your engine. Replacing the fuel filter is a regular maintenance task, and the procedure varies slightly depending on the year and engine of your Jeep Liberty. You'll need a new fuel filter and likely some tools (e.g., wrench, possibly a fuel line disconnect tool). Consult your Jeep Liberty's owner's manual or a repair manual specific to your vehicle's year and engine for detailed instructions.
* Fuel System Cleaning: If you're experiencing fuel-related problems (rough running, poor fuel economy, etc.), you might consider using a fuel system cleaner. This is an additive added to your fuel tank to help clean injectors and other fuel system components. It doesn't replace any fluid; it's a cleaner. Follow the instructions on the fuel system cleaner product you choose.
* Fuel Pump Replacement: The fuel pump is responsible for delivering fuel to the engine. If the fuel pump fails, you'll have serious engine problems. Replacing the fuel pump is a more involved process, often requiring specialized tools and knowledge.
In short, if you're experiencing problems with your Jeep Liberty's fuel system, don't try to "change fuel injection fluid." Instead, determine the actual problem (e.g., clogged fuel filter, faulty fuel pump, dirty injectors) and address it appropriately using the correct procedures and parts. Always consult your owner's manual or a reputable repair manual for specific instructions relevant to your Jeep Liberty's year, model, and engine. If you're not comfortable performing these tasks yourself, take your vehicle to a qualified mechanic.
