Now and again, usually after some freeway mileage, my coach will stall when starting from a stop sign or light. Symptom is, it pulls off OK, then - usually when it shifts to second - it simply quits. Sometimes a bit of a sputter, but usually just croaks. Sometimes it restarts immediately, others it takes five - fifteen minutes. When it restarts, it seems to go OK. I've installed an electric pump in the reserve line, hitting it doesn't seem to matter. The pump does help in other situations, heating on hills or idling in traffic, and priming to crank after it's been sitting for a week or two. I have a new and tested coil/module/cap which I think I will install. I'm also contemplating a second electric fuel pump and removing the selector valve. These are Mr Gasket pumps, with internal check valves. They're made for continuous duty for carbureted engines. I detest intermittent troubles (which the GMC seems to generate) because you really can't say "I found thus and such, did this, and fixed it".

--johnny