What too much crankcase pressure looks like

[firstv70volvo]

Here is a short video of a Chevy Equinox 2.4L Ecotec engine with a plugged up PCV system. I know it's not a Volvo or a turbo engine but Volvo's can and do have PCV issues, high crankcase pressures and blown seals if not maintained. The crankcase pressure gradually builds up to almost 2psi and what I found most interesting is the amount of pressure released when the oil filler cap is removed at the end of the video. This car (my daughter's car) has a horrible rear main seal leak when running and you can see why from this test. These engines are known to have PCV clogging issues and blown rear main seals, a very expensive repair. It's best to keep a good eye on the PCV system to avoid nasty repairs like this one. One solution to save the rear main seal for this particular engine is a vented oil filler cap that vents the crankcase pressure if it gets too high from a plugged up PCV system.
Why does it have to be the rear main seal that fails? The most time consuming and costly seal to replace.

[ignatz]

Put an air hose on the oil fill cap and inflate your tires!!