'93 4.0 Dies while driving - starts after a few minutes

[89RanBrII]

A friend of mine has a '93 that he recently bought. It has started dying on him as he drives along. When he tries to restart it, it just cranks and cranks. After a little bit, it will start and continue driving.
-4.0
-M5R1
-4x4
Does anyone have any suggestions?

 

[Uncle Gump]

When it doesn't start... be prepared to check for fuel pressure and spark.