ORIGINAL: unclezesta

os 18 tz and drive train upgrades. lol. but hey, about your engine problem...i know its a not-so-good engine and all, but from what it sounds like, you are tunning it when it is not warmed up, and once it gets up to temperature, it is of course out of whack. the only way to properly tune an engine is when it is all warmed up, because materials expand and contract at different temperatures, and the engine will do almost all of its running up at temperature. just my diagnosis, it probably this combined with other things like your fuel, or a possible air leak, or just the engine being sparatic in general.