It could also be an issue with where the trunk lid connects. The latch mechanism has two spring-flaps (I don't know what they are really called). They can break, or the spring breaks. That is the case with mine...The tension on the springs is released, but since one of the spring-flaps is broke, it doesn't push the door up high enough, then relaches in the half-closed position if you are not fast enough to open the trunk. I think the only way to fix this situation is replacing the entire mechanism. It is on the get-around-to-it list, but I have other, more important repairs to make first