Alright so, I have a 2011 Mustang GT 6M that I purchased used at 84xxx miles. At about 89xxx miles the CEL showed up and the only code is p0308. I knew this was a common issue on these cars but I checked the main things that it could be like changing spark plugs and such. I swapped the coil pack with cylinder 5 and later on it came back as p0308 again. Now i'm worried. The code seems to come and go. sometimes for days at a time it will be gone and wont even show up as a stored code. I have checked on cold starts and warm starts to see I can spot any blue smoke from the exhaust and keep checking up on my oil and its not burning it at all. So I really just want to know if this seems to be a cylinder issue because i definitely can't afford to rebuild or replace my engine :/ P.S- The only mods it has are an Airaid cold air intake, Airaid Throttle body spacer, and a BAMA 91 race tune. All of which were installed by the previous owner.