Since it acts up going one direction more than the other I would get a real good look at the F and R contactor. Did you pull it right out and check it? I know on that model it is almost impossible to take it apart still mounted in the truck. I just fixed one with that problem and it was the big spring in the contactor. It wouldn't push the contact armiture back enough to make good contact, when not energize, all the time. Once the card "sees" that, it trips the PMT off and you must reset the key.