HAd a car come through the shop with a n intermittent stalling problem. After a huge amount of time, removed fael tank, and drained. Tech found a ziplock bag in there. It would starve the pump for fuel, once suction was broken it would release and float around. It may take 10 miuntes, it may take 3 days before it would act up. Just thought I'ld throw out another reason there.