IIRC the only 'pin' on the tie rod end is a small cotter pin that makes sure that the nut can't loosen up or fall off and cause a loss of steering on that side. If the pin is missing, it could mean that the bolt on the tie rod end has loosened up, which could be dangerous. If the bolt is loose, tighten it up asap and put in a new cotter pin. (10 cent part) If the threads are damaged, you may need a new tie rod end ($30?) and an alignment.
