I have a model 917271920 wi th motor model # 407777 0167 E1 that is only running on one cylinder. I can disconnect the spark plug wire on one cylinder and it still runs, reconnect the other one and disconnect the side that it ran on and won't start. Tried starting fluid no results. Checked the ohms on the coil and both the same, am getting spark (weak) on dead cylinder but won't run on it. Any ideas??