The SES was on and off one day ago, nothing special on the car. I pulled it to Autozone to read the code out, it was P0304. One misfire was detected. Two years back, I had same issue and had probably three out of four EGR valves replaced in a shop. And also rewire the spark to 0.04. Last time, when I did the oil change, I was recommended to replace Valve Cover Gasket. Could this be related? I was told to perform flushing engine as well. And I think this is probably a minor issue to the car, no need for fix right now (till this weekend)?
