Has anyone had random misfires? They come and.go especially in start up idle. Not isolated to one cylinder so hard to swap coils and see if it follows. I sealed up a vacuum leak I had and replaced the MAF sensor. It worked for a day or so and came back worse. My engine light was flashing and one cylinder misfired close to300 miles while driving on the highway. Could it be a head gasket.? I do t have any other issues other than an evap code. Doubt they are related as I have had the evap code for over a year. Wondering if it's time to junk it. It's a convertible so it's a second car and not needed if it's going to cost a fortune to fix it. Every once in a while it will throw a cat code 16825 although I can get it to pass the test with basic setting.s. Any thoughts would be great. Thanks