Additionally, engine oil would drip from the road-draft ... Inspect the PCV valve by shaking it or by blowing compressed air ...

You take your car in for an oil change. The work is almost done when the technician comes out to talk to you. Hes holding your air filter and PCV valve and recommending that you replace both ...

All engines allow some exhaust gases, unburned fuel and oil to “blow by” the pistons ... which is a source of varying air pressure, the PCV valve maintains the optimal level of vacuum in ...