The Engine Computer has detected a problem, set a diagnostic fault code, and turned the Check Engine light on to tell you. There are over 2,000 potential fault codes. About half of them refer to things that could adversely affect emissions. Those are the codes that turn the Check Engine light on.
The place to start is by having your mechanic read and record the fault codes. Those will indicate the circuit or system that needs further diagnosis, or the unacceptable operating condition.
Thursday, December 29th, 2016 AT 3:28 PM