The Emerald Plus 4000 generator in our old '93 has about 300 hours, but I have had to replace plugs a couple times. It would be running fine, but on the next restart, perhaps months later would run very rough. Replacing the plugs would cure the problem. Had to replace a relay recently, but other than that the only other problem affecting smooth operation has been spark plugs. I could never understand the plug failure. Removing the plug wire and reseating it would not cure it, only a new plug.
Kevin n Chriss
2015 Newmar 3103 Bay Star -The Pay Car-
1993 Fleetwood 28T Bounder -The Flounder-