A 1g bottom with 2g top cant possibly cause the misfire code. That has nothing to do with it whatsoever. both heads drive the sensor in the exact same way. There is no difference in the two heads that could cause a code from one and not the other. That is typical bad information that shouldn't even be posted once much less posted and reposted like there was something actually to it. If your going to post such crap, at least give a possible reason why. I would love to here it.