Its simple, there is a metal clip roughly in the shape of a U that you have to push. When you push the clip you will see the sides of the clip move out and then the clip pulls off at the angle it attaches to the injector. The metal clips are not perfect and sometimes get stuck. A few of mine were stubborn and the metal clips took a decent amount of force to compress. Be careful if you break a injector you'll have to remove the fuel rail and install a new one. Dealer price $155 each.