check engine light is on intermittently. Occasional cut back when driving.

What is your question?

I had a new distributor and valve cover put in about a month ago.Right after the yellow check engine light came on intermittently. Also, sometimes I notice a slight hesitation when driving espeically in the mornings (it died once while idling)and sometimes when going a bit uphill. No starting problems, car can do 80 with no problems, however. Dennis