Q: It says service engine soon usually in the morning while warming up and goes out but does not come back on.

The check engine light should come on when you turn the key to the "on" position, but without starting or running the car. That function allows you to do a bulb check but also indicates that the PCM (computer) is in the circuit. Once you start the car, there should be no illumination of the check engine light. However, inasmuch as it has illuminated in your case, that likely means that diagnostic trouble codes have been stored. These codes should be downloaded and interpreted by a mechanic in order to resolve the underlying fault that is causing the light to come on. Consequently, your best option is to request a check engine light diagnostic. During such a diagnostic, a certified mechanic from YourMechanic would use a code scanner to retrieve the specific diagnostic trouble code(s) from your car’s PCM that have caused the check engine light to illuminate. Using those codes, the appropriate individual vehicle components or sub-systems (often a sensor, circuit, and the like) are tested to pinpoint the cause of the fault or the reason why the check engine light has illuminated. Once the faulty part or component is identified, it is explained to your satisfaction and the mechanic will let you know of the cost to repair. If you have further questions or concerns, do not hesitate to re-contact YourMechanic as we are always here to help you.