It is a plastic intake; nonetheless, there are few aspects that may be further deteriorated. The EGR pipe connects to the tiny ports on the intake and subsequently to the manifold. Seafoam is formulated particularly for injector cleaning, making it entirely safe for use in cylinders. The obstructed channels undoubtedly expelled debris and carbon along with the Seafoam. I removed the spark plugs and cranked the engine, which expelled the debris from the top of the engine instead of obstructing the catalytic converter. Upon reassembling the EGR and reinserting the plugs and coils, I emitted a substantial cloud of white smoke.
The vehicle is operating much better; it has not shown rattling throughout six cold starts, the persistent OBD misfire errors have been eliminated, and power has been enhanced.