(assume you are talking an automatic?) I have not heard of a bolt doing it but on one of mine the bushings on the selector rod had both worn through and it wasn't moving enough to go into reverse and if I jiggled the shifter then it went straight to neutral, also had difficulty in going to 1st. a pair of new bushings for about $10 and a barrow full of pain and suffering got them installed and sorted the problem mine happened hot or cold though
cheers
barri