I swaped in new plugs this weekend, I took a quick look in the cylinders while the plugs were out, and it was solid carbon black. I pulled the air filter, the TB was also coated in black carbon. I looked down in the intake and it too was black. I just ordered a new AEM dryfow to replace the existing COI, and will be swapping it in when received. The question is; do I need to run a carbon cleaner like seafoam? I have been reading up on this and there seems to be two schools. One says the seafoam is the best thing since sliced bread, the other school says it is not needed and not good for the motor.