I have a 89 F150 with a 302 5.0L V-8 I just bought this truck and it will run fine untill i drive it for about 15 mins and then it will act like it is out of gas when it is not and just quit it will not even start untill it cools way down also i have noticed white smoke comming from under the oil dipstick when it gets warm.... any ideas of how to fix this problem?