Hondata

Car: Civic Si 2018
Mod: 27WON intake + flashpro

Everytime I turn off my Cruise Control Main to disable the revhang, sooner or later I get a P0299 code. I know I should disable this P0299 code via flashpro. But if this code is disable, do I risk to miss other problems that could hurt something else seriously?

It is an underboost error. It occurs when the boost tables have been raised higher than what the turbo can provide, especially when spooling. Disabling it in itself will not cause any problems, the only downside is that you might miss a boost leak if you somehow split a hose etc.