power flickers when a/c kicks off...(Not on) 3 times now.

136V is pretty high nominal voltage, particularly with a little bit of voltage drop in a reasonably long cord. I would check for a loose or poorly connected neutral somewhere. If it's a 30A (or 20A) outlet you're ultimately connected to, that would pretty much have to be at the panel input or, if wired from a subpanel, in the feed from the panel to the subpanel. If it's a 50A circuit feeding you, it could be anywhere from within the RV back.