Our engineers at Mishimoto are no strangers to the dangers of oil blow by. We have well-documented evidence that this is still a common threat to most modern direct injected vehicles. For those of you that don't know, blow-by is a byproduct of compression and combustion. Blow-by is created when oil and fuel vapors push past the piston rings and into the crankcase during compression. To keep the crankcase depressurized from this oil and fuel, there needs to be some sort of venting. This is accomplished by routing this blow-by through the intake tract and right back into the cylinder to be burned during combustion.
Even though this particular engine uses port injection, which sprays fuel directly onto the valves, the problem still lies within the venting process. By rerouting blow-by through the intake tract, there is a potential for accumulating carbon deposits on your valves in addition to a nice thin coating of oil along the inside walls of your intake (and turbo if applicable). The
