The burner tube and all inside will need to be taken apart enough to find out what is affecting the air gas mixture. In mine it was a spider web that pressure would not touch. Another time the orifice was open to the eye but running a thin strand of copper wire cleaned out whatever it was and it worked perfectly afterward. I was able to remove the gas line and take the whole end out from the regulator to the orifice for inspection and cleaning.
One caution, do not enlarge the orifice opening.
I have heard of dirt dauber nests in there also after a winter storage.
Sounds like it needs a little elbow grease applied to it.
2011 351RLTS Eagle, Mor/Ryde suspension & pin box
06 F350 Lariat PSD, SRW, LB, CC, EGR delete kit, 16K DrawTite hitch, Timbrens, TST TPMS
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