the check engine light only comes on when the onboard computer detects a fault in either the engine management system, transmission, or emission control system. Faults can range from vacuum leak, engine misfire, transmission problem, emission control leak, one of dozens of engine or transmission sensors, or even internal engine or transmission failure. There are over 500 fault codes that can cause the check engine light to come on. And not every one has symptoms you can feel or see or hear.
The only way to determine which of the over 500 faults is responsible is to have the onboard computer read with a diagnostic scanner. once this is done and the fault code retreived then pinpoint diagnosis can be done and repair done.
without knowing which of the over 500 faults is responsible, it is simply impossible, as well as irresponsible for anyone to guess at to which one is responsible for the check light coming on.
Unless you live in California, you can run your car by any major parts store and they will retreive the fault code and definition for you for FREE. At that point, you can decide if this is something you can repair yourself or have a professional do the repair?.
Please remember to rate service using the rating page so that I may receive credit. Thanks
If for any reason, you can't rate my answer OKAY, GOOD, or EXCELLENT today.
Please reply and let me know why, so I can help more/better.
All follow up responses are FREE, after completing the required rating
Please note that if you have a subscription service, you still are required to rate service, however you are not charged again. This is just so that your expert is credited for their time and services. Thank you.