Heres the deal. Its a 97 Tahoes 2dr Sport with a 5.7. As I was driving one day, I was feeling a little sputter from the motor. Kinda like a misfire of some kind. Then it stopped. I thought it was bad gas or maybe some water in the tank so I added some cleaner and dry gas. The next day I go to start the truck, the motor was cranking and it locked up for a second, then started cranking again. It locks up here and there but would not start. I didnt get to mess with it, tried it a few days later and it started, but ran with a sputter again. I tried it tonite and it wont start. I still havent touched anything. Any ideas on where to start? A check list I should go by. Thanks...