Wife's Pathfinder oddly enough at times seems to have an idle problem, Only does it on occasion and watching tach, doesn't reflect a miss. Inside car you can hear what sounds like a miss through dash area with a slight rattle sound. Nissan says twice they can not detect problem, however, with service mgr in seat while it was doing this, he told us nothing could be detected. Wife and I just looked at each other since we both thought he was questioning our senses. Any suggestions? Otherwise it's been a great car.