Check engine light is on.

[mazenb9981]

While I was driving back home from school tonight my check engine light came on when I was pushing the car alittle. But everything else was fine. The only time the check engine came on was when I put a massthunder muffler. I think the mechanic pulled the o2 sensor alittle too hard. but after the car ran for 15 min, the engine light went off by itself. and now after a week it came back on and it still on. I am driving a 99 eclipse RS nonturbo with cold air intake. Any help to let me know what might caused the light to come on. Thanks

 

[luv2rallye]

Take car to Checker Auto (or other auto store) where they will read out the diagnostic error code for free.

 

[mazenb9981]

the light went off by itself. why???

 

[luv2rallye]

The abnormality probably ceased but the error (or trouble) code usually is still retained in the ECU and can be read out.