I`ve had the low ruff idle issue, mostly in cooler weather, another thing I`ve noticed is going down long hills decell, come to stop sign, take off and motor feels very lazy till about third gear, I almost think it`s something with retarded timing, I have heard the timing retards on decell so there`s not so much backfiring, seems like timing doesn`t advance back till you rev it up, for other that have high idle, timing could be little advanced causing high idle, I don`t know, just a thought.