Well, i have a cilinder 1 missfire code, my wife had placed 91 oct on my car which is tuned for 93 oct, it was driven hard and according to bama it could be a spark plug that went bad or the coil, i replaced the spark plug and the code is still on, could it be i have to replace the coil as well? I dont want to just buy the coil which is 70$ and not solve the problem? Anyone else hd this issue in the past? The engine does kind of like a lagging sound.

 

Engine is lagging kind of like if it had cams

 

Swap the coil to another cylinder. Clear the code. See what happens. If the misfire moves with the coil... You have a bad coil.

 

Great! What if it keeps showing the misfire, what would be the next step? Check injector?

 

I may be wrong but I think an injector is unlikely. Coils in my experience have a much higher failure rate. Technically you could do the same procedure though with swapping injectors.

 

Thanks man!

 

If it's not the coil it could be misfire TSB:
tsb13-06-15.pdf

 

What is missfire tsb?