Sorry to hear you're having troubles getting your Mustang to start. It's really strange that you had no issues the first day and now it's only starting with the stock tune. Are you making sure the dial is set perfectly on each tune and not in between two numbers, by mistake? I would also check all the connections from the dial to your PCM and make sure they're secure.
Let me know how if that helps any. Keep me updated, I want to make sure you're all taken care of!
Shane Lesky | AmericanMuscle.com
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