Oman 5500 only runs for 10 seconds and shuts off?

We have a 2011 Onan 5500 RVQ and just got home from a 2k mile trip and it ran flawlessly. Litteraly as we pulled into town with the A/C's going cause it's 110 degrees the generator shut off and we could not start it again. I figured it was the fuel pump so I swapped it out and now it only runs for like 10 seconds then shuts off. One time it ran for about 3 minutes but then shut off. Before I swapped out the fuel filter it would crank over but would not run at all. I figured it had to be fuel but the fuel pump
Swap hasn't helped. We ran the generator probably 70-80hrs over the past 3 weeks without issue. I'm stumped and we are trying to get out of town again and nobody has time locally to look at it. Any ideas?