My 93 80 does not want to go if I leave it idling in park for more than a couple of minutes. If its in drive it will not do this, I changed the filter and fluid and the symtoms did not change. I really have to give it some gas before it wants to go. I have taken it on 500+ mile trips with no issue. Any ideas? 178,000 miles on the clock no previous maint. records.