larry r, what you describe sounds pretty normal to me. I had a '88 Superchief with a 4K (or 4.5K?) Onan, and it surged for a bit right after start up. I always let it "warm up" for a good minute or so before I put any loads on it. And when I did kick on the AC, yes, there was a surge again, I'd say a couple times over a 5 second period, then it steadied right out. RV Wizard's note about carb cleaning is good; just dump the cleaner into the coach tank (several bottles depending on your gallonage) and let it work thru the system for a couple days. Last thing, I'd advise you not to tamper with carb screws/settings, linkages, the governor, or trying to tweak the engine speed; those are best left to Onan techs using meters to get it tuned.
Last Brave 2004 34D