One side of the range does not want to light. There is spark but sometimes it appears not enough gas. If the burners are set just right rotating the knob to light burner back and forth with gas on it may finally light. I'm just curious to know if the problem could be a faulty orifice tube assembly.
If there is a gas flow issue then the issue would not be in the tube assembly but the orifice may be clogged or the ports on the burner. You will want to check the burner to make sure that the ports are not clogged. It could also be a issue with the gas valve for the unit but if both sides are the issue then it may be that the igniters have been shifted while cleaning and need to be adjusted.