Here a "copy" of my answer to another post (for a trouble shooting suggestion):
There appears to be a few of these problems on this site for 1990s model Dakotas. If yours is like my 1992 Dakota (and a few others) it will stay broke for a day or two and then magically start working normally. I have changed all the sensors and computer and it still acts up intermittently.
QUESTION: I noticed on another post that the Dakota owner would sometimes have to move the shift lever from PARK to NEUTRAL before the starter would engage (indicating that the neutral safety switch is acting up). My Dakota does the same thing occasionally. Although I do not understand why, someone has suggested that the neutral safety switch does have an input into the computer's control of the engine spark. Does your Dakota have a problem with the neutral safety switch? I may change mine to see if it makes a difference.