1990 geo prizm 4 door hatchback LSi with a check engine light on you have tried to pull the code jumping the diagnostic terminal under the hood with no luck What if the check engine light just remains?

As long as it's running okay, don't worry about it. You could try disconnecting the battery ground cable for a couple of minutes and see if that clears it. Cars are programmed for the CEL to come on every once in a while just so you'll take it somewhere and let someone cheat you out of some money just to tell you everything checks out okay. What a con game.