Hyundai Repair: engine light on, noise sound, trouble code

Question
2000 tiberon
i heard a noise sound like a flapping, then as i drove it lighten up and the gears dont seem to kick in, it sem light an electrical problem, what can this be? and is it costly? please

Answer
I'm not sure exactly what you mean by "lighten up" or "gears don't seem to kick in,"  but the most direct way to get an idea as to what's wrong with your vehicle is to check the diagnostic trouble codes.  If your check engine lamp is on, there should be a trouble code which will reveal the nature of the problem witnessed by your computers.  At this point, the cause could be just about anything and the cost could be inexpensive to extremely expensive.  That's why you'll need to check the codes.  

I should be able to give you better information once you have the trouble codes.  Auto Zone has advertised they'll check codes for free, so you may wish to give that a try.