Fuel injectors were leaking. Replaced. O-ring split on install (without knowing). Gas filled (gallons) exhaust system. Fuel was leaking everywhere, blasting out tail pipe, blew a bunch of carbon out. Replaced o-rings. Changed spark plugs. Changed oil filter, replaced oil. Still ran rough. Fan was kicking on when it shouldn't (54 degrees out). Thermostat froze, replaced thermostat. Flushed radiator, replaced coolant. Rough start, once running it runs smooth on the freeway, no missing or anything. Starting scares the crap out of me. Check engine light comes on. It's throwing a code saying fuel to rich (or something like that). Planning on replacing the oxygen sensor. Any other ideas?