Originally Posted by Jagspe
Thank you for all your help. I have more information now. I put some cleaner in the gas tank that was recommended by Onan with no help. I tried to run the AC again, and this time I noticed a clicking noise coming from behind the fuse panel. It sounds like a turning signal. What can that be? Can that be the issue that I am having?
I wonder if your fuel pump isn't going out like I believe mine is (also have an Onan 4kw). I'm taking mine in tomorrow to get it checked out. It behaved similar to yours, at high altitude and hot. I used to hear a ticking sound during priming, but from what I understand, it should be more of a thud sound. Mine will run fine right now and run the AC, but I'm guessing it'll shut down again if I start driving and its 100F out. I also have to prime it 3 times or so before it'll start. Hence I'm leaning towards a bad fuel pump. We'll find out tomorrow and I'll keep you posted.