Got A 98.5 A4 1.8T QMS with about 100K on the motor. Right now I am running an APR Stage One chip with a stock k03. I suspect that sometime in the future I will hearing the sound of a dying turbo. My question is "can I replace the k03 with a k04 and use the same software"? If so, what other changes will I have to make.

1998.5 A4 1.8t QMS, 228K and counting, 300k or Bust!!

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