How to Fix Error Code P0172 | [nonda Auto DIY Center] P0172 is one of the most common engine error codes, it stands for [System too Rich (Bank1)]. It indicates one of
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HELP CEL ON: Rich at idle bank 1 and 2 / Lean under load bank 1 and 2 - 6SpeedOnline - Porsche Forum and Luxury Car Resource
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