Poor original poster ILV2RK, this discussion has gone way beyond his original inquiry. Most people do not know the intricacies of scanner programming and don't plan to. ILV2RK, the 4.2 VVT is notoriously sneaky to diagnose. It could be the chain, too. I would recommend adding marvel mineral oil to the engine (half a quart) —sometimes the VVT valve itself sticks due to the oil screen on it clumping up.