Ever notice that nice layer of oil caked inside your intake tubing and intake manifold? Yeah, that’s thanks to your car’s stock PCV system constantly routing a nice fine mist of oil right into your intake tract every time you drive. Over time, that mist will grow into a nice buildup and could start to hurt your car’s performance. Now, don’t run straight out to your car and yank off the PVC tube, because the system does serve a pretty important purpose. Using the intake system to keep a slight vacuum on the crankcase at all times helps keep a better seal on the piston rings, and helps to vent the crankcase pressure.
In this video from Moroso [1] you can see firsthand just how much oil can be pushed through the PCV system even under normal driving conditions. For the video [1] the guys at Moroso [2] built a clear-bodied Air/Oil Separator and hooked it up to a 24,000 mile, bone stock, LS6 equipped Cadillac CTS-V and took it for a spin. The video’s caption tells us, “You can see a puff every time I lift, and oil running down the sides under hard acceleration and heavy downshifting as well as at the end when I am just driving back to the plant. [At] 1:24 I am downshifting and it pulls a lot. [At] 3:14 is a long acceleration and lift and it pulls a lot. Under normal driving conditions, (driving like my Mom) I get about 3/4 of an inch of oil in a week. I think you get the idea.”
Check out Moroso’s website [2] for more info on Air/Oil Separators.
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