Not that I would ever recommend doing so, but how could bypassing the PCV system NOT prevent intake valve carbon build up on a DI engine? With no PCV vapors, all you'd have is filtered air rushing across the intake valves on a DI engine (with no port injectors of course).
The only thing I could think of is combustion gasses getting upstream of the intake valves if/when there's any valve overlap called for.
My fear with these spray cleaners is, when done often, they may take a bit of life off the catalytic converters with each use.
The only thing I could think of is combustion gasses getting upstream of the intake valves if/when there's any valve overlap called for.
My fear with these spray cleaners is, when done often, they may take a bit of life off the catalytic converters with each use.