Service Engine Soon Light?

[L McIntosh]

Yesterday when I came to a stop at a light, I notice a uneven idle. As I took off from the light the Service Engine Soon Light came on. At the next stop light the idle was back to normal, smooth. It was very hot out, but the engine temp was not hot. I drove it home, and today started it, and the light was still on. I had a 1/2 a tank of gas, and I then took off the gas cap. I sure don't want to take it in the reset the light. Any thing I could do to fix this myself. My vette is a 1996 CE LT4 with low miles.
Thanks Larry:)