I own a prelude with a h23a. I've been running with a messed up ignition coil for i don't know how long, and code 12 pops up whenever I drive on the freeway.

One thing is that it comes on sooner or later depending on what city I get gas at. I have tried cleaning the carbon out of the passage, and it helped, but then it got worse again. I think maybe cuz of the coil, it is putting alot of unburned mixture in there causing it to clog. Any input would be great.