Nissan Repair: 97 altima check engine light, gas cap, autozone

Question
My check engine light has been on for a couple months now.  When I took my car to the repair shop they said not to worry about it (kind of weird).  Yesterday while I was driving to school, the light began blinking a few times then stopped.  My check engine light color is a yellow-ish color.  Am I looking at spending a lot of money for fixing this problem?

Answer
Sean,

Take your car to Autozone or Checker and get the code read for free and email me back with the code.  I am surprised that the shop did not give you the code to let you know what the problem was.  True, it could be as simple as a gas cap not being tight.  But, it could be something else.  The color of the light is unimportant.  But, that it is on is a problem and the computer has read and stored a code.  Have it checked and email me back and I will let you know if it is a problem