'92 Coachman Chugs & Stalls Cold Gas to Fix - Another Way?

Stim wrote:
When it acts up stop and open gas cap and listen for vacuum sound.
Might be a problem with fuel vent system (emissions). ??

Yes, this came to my mind.....negative pressure inside the fuel tank.

When it happens again, take off the gas cap to neutralize the pressure in the tank, put it back on, and see if the problem can be repeated with the same band-aid solution.