Many critical problems can go unnoticed, and are almost impossible for even a certified technician to pinpoint without a professional diagnostic tool. And if your check-engine light is on, engine diagnostic services are the best way to determine exactly why.

There are a number of possible reasons for an illuminated and/or flashing check-engine light:

- Overdue for oil change
- Sensors or brake system require adjustment/reset
- Engine, electrical or vehicle computer issues

Your vehicle provides key information in dashboard lights. If the check-engine light is illuminated, you should take your vehicle into service as soon as possible.

However, for optimal vehicle safety and reliability, engine checks should be a part of your annual vehicle maintenance, even if no check-engine light is on or flashing.