Puffing from VP 3.0L Oil Filler Cap - Normal?

[happycamper]

Today I notice that if I remove the oil filler cap on my 3.0L (while idling), there's a fair amount of air pressure that comes from valve cover.

I'm inclined to not worry about it since the engine runs good and delivers 4400rpm/35mph at WOT.

Should I be concerned?

 

[blueoval1]

Re: Puffing from VP 3.0L Oil Filler Cap - Normal?

I'd run a compression check for the heck of it. Is there any condensation on inside of cap?
If cylinders check out , and no water in oil I'd say .....If it ain't broke , don't fix it!!
BTW , where you at in Colorado? Salida here!