[dave in australia]

I suggest checking the fuel tank for moving sediment. I don't think the crab apple comment is far from a possibility. Had a friend whose suzuki 4WD would run and then die, anywhere, anytime. He tried al sorts of things, including blowing air back along the fuel line. After lots of carb replacing and ignition system replacing etc, he pulled the fuel tank out, and emptied the contents. After the fuel came out, there was a rattle in the tank. He chased the source of the rattle, and it was a small petrified skink lizard. It would move around the tank and randomly block the fuel pickup in the tank. After letting the car rest a while, there would be enough fuel getting past the lizard, or the lizard would shift away from the pickup, allowing fuel to flow again. Not say it is the problem, but something to check.