2001 Chevrolet Cavalier, chevrolet cavalier, gas mileage

I don't have an owner's manual. On the dash a light came on that says check and a picture of an engine? Is it o.k. to drive or could something serious be going on? I was hoping to sell it before I put any money into it. It's been running fine, but recently it started making a high pitched noise and just before the light came on I applied my brakes quickly, lots of wet leaves on the ground,and the brakes felt really weird, like they were going to lock up or something. Any info that you can give me would be greatly appreciated.  Thank you!

Answer
    That weird feeling in the brakes on wet leaves was your anti-lock brakes doing their job by not locking up and hurling you off the road.  The light is your "check engine" light.  It means that something is wrong with the engine control system.  In order to find out what, you will have to get someone to plug a scanner into the diagnostic connector and read the code.  Even after that it may take some additional work to determine the real problem.  Many of the "problems" don't affect the way the engine runs, but will generally reduce gas mileage a little.  If it is something peculiar and expensive to fix, then let it go.  Selling a car with the light on is really hard, though.
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