I am alittle desperate on this one. I am driving along just fine and all of a sudden my suburban quits. it immediatly starts and may die again a few minutes later. then it might run fine for the next 20 miles. I changes the filter. i have had problems with the fsd in the past and put the heat sink in but this happens when the engine is cold. the fds problems i have had in the past have only occured when the engine is hot. there are no fault codes set. I was getting ready to sell the vehicle but can't feel good about selling it with a problem like this. Any ideas from you experts?