Hi I'm new to the forum. Bought an '08 ForTwo just recently. A Check engine light came on the other day, I had the code read and reset. It was p301, indicating a cylinder 1 misfire.



I installed new spark plugs. I noticed the ones in it were not stock. They look like iridiums, and seemed pretty new. The gap was not correct though, so I thought that may have been the issue. I rotated the coils too, reasoning that if the CEL comes back on a new cylinder, there may be a coil issue.



After resetting the code, I drove ~200kms, mostly highway with no code. This morning, after starting up the car, the CEL returned.



Besides a potential coil issue (which may be revealed when I can get the code read again), does anyone know what would be a likely cause of a CEL?



I also put some seafoam in the gas after the CEL, before the 200 km trip, thinking something may be dirty or maybe there was some moisture in the gas. Any help would be appreciated.



Edit: forgot to add, the car is an '08 with 67,000 Kms. The car seemed a little rough, especially at idle before resetting the code and switching the plugs. Seemed better afterwards, but that could be in my head