Your check engine light comes on, maybe at the end of a long drive, or as you start your car to leave for work. Your car is telling you something! Some dashboard indicators are pointing to an immediate problem, but how can you tell?
Not an immediate concern, but check with your mechanic if you check engine light is on and:
Car is not making strange noises
No smoke is present
No strange smells or odors
Gas mileage is usual
Car seems to be behaving normally
Immediate problems that should be checked with your mechanic right away: