sputter and code p0304

[aaparker]

Just recently I did something dumb. I mixed a 20 percent methanol solution for racing in my 2g. The car ran fine for a bit, it then began to sputter and vibrate real hard. I tried to gas it to a place where I could pull over, it wanted to die but I got it over. I let it idle for a bit then the sputter went away and drove fine for a bit after that. I went and topped off the tank with regular gas which left the percentage at 10% or below. I have continued to drive the car and experience the problem only every so often. I have continued to dilute the mixture, but I am still having the problem and have also thrown a misfire code on the fourth cylinder. My knock had been increasing for some time before this and it has only gotten worse. I have performed a boost leak test, cleaned spark plugs, re-gapped them, checked wires, I figure I damaged something else but am out of ideas. Any help would be greatly appreciated. I thought I had it fixed so I did a 1g throttle swap but I don't want to increase the length of this post. So drill away.

 

[DSM4me44]

You are throwing a code for a "cylinder #4 misfire"

Check your wires and replace your plug(s) and reset your check engine light. See if that helps. Sounds like you blew the gap out on your spark plug. But since you regapped them, id throw in a new set.

 

[aaparker]

Thanks I will definitely replace the spark plugs, like I said I cleaned and re-gapped the plugs, I did reset the light but it threw it again. I have a lot of oil in my system, every time I pull the plugs they look pretty bad. They have black soot and a hint of red carbon build up. I think the red build up is the way the octane booster burns off onto them. Any other suggestions would be helpful, thanks.