check engine light on 1998 Plymouth Neon

what could be the problam with the check engine light staying on.can't get car inspected

2 answers
Clean the gas cap gasket and the gas filler mouth real well. Worked for me.
There can be many many reasons for a check engine light coming on, just look at this list of codes that will turn it on:
Do you know which codes your vehicle has stored in the engine control module?