service engine light

We have 1999 Intrigue. The other day while traveling down the highway the service engine lt came on . The owners manual mantioned gas cap inssues ect. I called the dealer and brought it over for a diagnostic check. The said it had a EGR? code 167 miles ago. Which would be about right. The light came on and stayed on. He said possibly a valve in the emissions was faulty. On the way home I stopped from gas, filled the tank, and while driving home the light went off. I called the dealer and explained this. He said to watch it. I had already made an appointment. Was wondering it I should bring it back in, or did this problem possibly go away?

Thanks

The loose gas cap logs itself as a problem in the evap circuit. If the PCM is logging a failure in the EGR system then it is a different problem.

If the light comes back on it is probably a real problem. The good news is that EGR failures will not typically leave you stranded on a dark road somewhere.