Well I hate to BUST every bodys bubble but I JUST went through ALL of that and in the end IT was the fuel pump.2011 is to new for bad fuel line.I went to amazon and ordered a AIRTEX E11015 Fuel pump,which is the exact same pump for my Onan 5500 Gen.It cost 45.00 not 125.00.took about 1/2 hr to replace,while i was at it I put a inline fuel shut off on,and removed the fuel filter at the carb, Onan said you don't need two filters.the fuel pump was cheep enough I bought a spair.its worth it to keep on hand, because if I need one i won't have to wait to have one shipped .