Sounds like you got the plastic quick connector off so here is how to remove the metal quick connector, this one requires a special fuel line disconnect tool which your local auto part store should have.
Remove any dirt from the quick-connect fittings.
Wrap shop towels around the hoses to catch any spilt fuel.
At the fuel rail, push the connect fitting toward the fuel tube while depressing the built in disconnect tool with special tool 6751 or equivalent. To disconnect the fitting from the fuel rail, slightly twist the fitting while maintaining downward pressure on the special tool.
Cover the fitting to prevent any contamination.