Have a 06' SS/SC that will turn over till it times out. Loads up with fuel just acts like it's not getting a spark. You have to turn it over until it hits and then the engine knocks and feels like it is coming threw the hood. You then have to unhook the battery for everything to reset and then crank the car. No codes are thrown. This happens when the car feels like it once a day, three times a day, once a week, no patterns. Leaning toward a pcm problem. Any suggestion would be appreciated. 2.8", 60's, CAI, H/E, HPTuner

 

Check your coolant temp signal when it acts up, could be reading to cold and dumping fuel.