Park your vehicle on a level surface and turn off the engine. Engage the parking brake and chock the wheels to ensure the vehicle doesn't move while you're working.
Locate the fuel filter on your Ranger. It is usually a cylindrical metal object located near the fuel tank.
Once you've located the fuel filter, use the fuel line disconnect tool to release the fuel line from both ends. On a 1999 Ranger, these should be plastic, not metal, connections.
The tool has two forks that you insert into the retaining clip on the fuel line.
Squeeze the handles of the tool together to spread the forks and release the clip.
Gently pull the fuel line off the fuel filter. Be careful not to spill any fuel.
Repeat the process on the other end of the fuel filter to disconnect the other fuel line.
With both fuel lines disconnected, you can now remove the fuel filter from the vehicle by unscrewing it from the fuel line bracket.
