Hello, doing your own search is always better and efficient than relying at the mercy of workshop be it dealer or outside guys. Let me tell you that check engine light can appear for 100's of reason and reading forums and doing something might not be applicable. First can you tell any other symptom like shaking, stalling, hesitation etc you have noticed since check engine light has come? If not then for sure i highly advise you to get the car computer check up that cost 100 dirhams but it can pin point in exact direction, whether its exhaust issue, sensor issue, fuel issue or anything else. Once you get the fault code that is causing check engine light then you can dig on that fault code and understand what need to be fixed. Engine as a piece of metal have nothing inside (majorly) that can cause this light to appear. Its usually sensor and electrical stuff that support engine freak out and this light appear. In some reasons if fuel cap is loosely closed that can cause some air in fuel system throwing this light to appear.