Oil under Air Filter in 1991 Nissan Truck

1991 NISSAN TRUCK
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WTURKINGTON
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I have replaced the PCV valve but am still getting oil blown over from the valve cover into the air filter housing. It pools there and drips out slowly.
Jun 29, 2007 at 8:08 PM
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2CARPRO JACK
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Sounds like you could have what is called "blow-by" On higher mileage vehicles or ones that have been stored, the piston rings will wear or lose their "seat" causing compression to pass by them, pressurizing the crankcase. The only outlet is to push it out the breather into the air cleaner
Jul 1, 2007 at 8:18 AM
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