I have a 96 blazer was having a hesitation problem when i get around 50 mph. I thought for sure it was my fuel pump so i picked up a new fuel pump. I dident get a chance to put it in yet, but a freind of mine who is a mechanic suggested trying to cleam the mafs sensor with some carb cleaner first. I tried that about a week ago and the problem seemed even worse so i bought a fuel pump. I diden't use the vehicle for about a week and it sat in the freezing cold and i dident get to changing ther pump yet. I had to use the vehicle today and when i drove it into town and back it ran perfectly no hesitation? Is it possible the carb cleaner took a while to work and now it fixed itself? Thanks to anyone that may have some ideas.