I just changed my plugs and when I finished I started the car it was running rough and the engine light came on. I heard a constant ticking noise and look under the hood. One of the wires was loose. I made sure to put the wire back in tight and started it up again. It ran pretty and sounded pretty good. Every thing seems to be working fine but the light still comes on.

Any Ideas????

 

If the SES light comes on, then a trouble code is set, and you can read it with a scanner. The problem is probably a misfire due to a bad connection in one of the wires. If your car is '97 or later you would have an OBD2 computer, and it can tell you which cylinder is misfiring. The OBD1 only tells you that there is a misfire, but not which cylinder.

 

Will the OBD2 computer reset the code?

 

You can reset the computer by pulling the PCM BATT fuse for about 30 seconds.