Car Won't Stop Misfiring
i have a 2009 cobalt ss. i have been taking it to the factory for the past month now and i've been there a total of 4 times. going to be my 5th. they have replace my injectors and even installed new spark plugs and a coil in cylinder number 2. I picked it up last night and now this morning the check engine light came on again. i hear popping from the back of my car as well so i know the code must be for misfiring since it's backfiring. has anyone had this problem before?
I have 24,000 miles on my car