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The "engine light" being aglow for a short time is a precursor of things to come - a very early warning system.
Have the codes read - this is the prevailing sentiment on this site.
IMO, do not disconnect the battery, and do not ignore the lite.
The CEL, emissions systems are still in their infancy, in great need of improvement, and this will come, not in my time(nigh zero emissions controls)but maybe in our children's time(nigh 99.997% control of emissions)....