Not sure if it will throw any codes but your speedo and shift points will be off, effecting overall performance. A retune is definaley needed. Tire OD and gear ratios are the first things asked for, atleast by EFI Live when opening up to tune.
Well the speedo and odo did get thrown out by 10mph which made for a 90mph speed limiter. Other then that it was just the annoying factory tune crap. All said I don't regret my order of things, but if I could have got a tune sooner I would have.
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