1987 Mazda truck problems

Hi, I have a 1987 mazda b 2200 truck 2.0 litre 5 speed sometimes when I start it t will idle for a second then shut of do this 4 or 5 times then crank over starts and runs.That problem just started prior to that sometimes I would be driving down the highway and truck would go dead pull it over and try to fire it up and it starts back up.Any ideas what would be causing this?Problems are probably related.Thanks in advance