Hey, I bought a bike and haven't been using my car much since. I was starting and using it from time to time to keep the battery and alternator going alright. A very very busy week went by without me touching it. I turned it on and it was sputtering and the check engine light was blinking. I turned it off a minute later. It only had 15 miles til empty; so I ran and got a gallon(2 days later). Attempted to start it and it wouldn't start....do you guys reckon it's cylinders or spark plugs...I'm not the best at this+I don't have much time. Thanks!