Started car up yesterday and it was running a little ruff. Took it around the block to warm it up and it threw a check engine light. Got it home and pulled the code and it was a P0301. Cleared the code and took it for another drive. Everything seemed to be running fine after that. After a few hours I decided to take it out again to see how it was running now that it cooled down again. It seemed to be running ruff again but never threw a code so I just took it home so as to not cause any damage. So where do I start, plugs, coils, and injectors?

Here is what my car has
Dw1300 on e85
Fp Red
AMS intercooler/piping w/tial
AMS dp and cat less turbo back.
BR double pumper

Any advise would be great

 

It's cylinder one, so I'd start looking at the plug, coil and possibly the injector, in that order.

 

Ya that's what I thought, not to ask a total knob question but which side is 1. I did a search and haven't seen much on this code.