There's Nothing Positive About the 2.0L SkyActiv PCV System! – JBR – Aftermarket Parts & Accessories
Engine Problems: Skyactiv Major Carbon Build-up | Mazda World Forum
The worst one I've seen so far - Skyactiv D carbon build up : r/Justrolledintotheshop
JTech Autoserv - Another one Mazda 3 Skyactiv visited for intake valve walnut blast to de-carbon. Rejuvenate the driveability like new car. Rm480, walnut blast, incorporating with LiquiMoly carbon cleaning liquid. Refine