What you are feeling is crankcase pressure. Every motor has a little blowby pressure because the piston to not fully seal against the cylinder walls. A little pressure is fine, but if it is excessive you may have an engine problem or a failed PCV system.
First I would check to make sure that the pcv valve and hose is functioning properly, and if it is, I would do an engine compression test.
Monday, February 16th, 2009 AT 8:52 PM