gmc yukon 2004. runs perfectly fine but about every other week it starts doing this mysterious start-stall routine. you start the engine, normaly one touch, and then it immediatley stalls. if you turn off the egnition completely, wait a few seconds, and try again it starts right up. it will continue to have this problem for a anywhere frojm five to ten of the next starts, then the problem goes away for another week or so. been doing this since we got it. have taken it back to the dealer at least five times and they cannot seem to figure it out. out of desperation i talked to a radio talk show guy about this and he never heard of this issue, and suggested it might be an up-date in the software but the gmc dealership didn't know of any up-dates. anyone know anything about this kind of problem with a gmc yukon.?