I just got an 18 gt yesterday and decided to tune it today. Goes through all the steps, now cranks but wont start. Gives me mileage, not flashing any alarm code. Only code in sct is 315 crank learn. Can't do a crank learn if car doesn't start. Flashed it back to stock same issue. Currently I have the negative cable off. Any other ideas, besides getting with SCT next week?