CCV question

Just a quick question...I replaced the valve cover gasket & CCV valve (it was pretty dirty, Let me just say the CCV is a PITA to get out...lol but on with the question, I used to get a "chatter" type sound kinda like a diesel that would start right after start up and continue for a few minutes then go away, I considered this to be piston slap the engine also had a very slight "tick" I figured this was a lifter or two making noise hey it happens with high miles and is almost considered "normal" with these 4.0's. After installing the new CCV and new gasket all that has gone away...I noticed it was not doing the chatter thing right away and the engine runs smoother and with NO lifter noise, I know the gasket would have nothing to do with this and didn't think a CCV could make that much difference but its been a week now and NO noises have returned it runs and sounds GREAT! whew...now after all that, can anyone tell me why this would make this much difference in the running of the motor??? I know...don't look a gift horse in the mouth BUT...

I cannot tell you why, but that crank case does much better when properly vented. In fact, drag engines are frequently hooked up to a pump that pulls a vacuum on them.

Not sure how either, but hey...It's running and sounds great this thing has never been so smooth and quite, Just seemed like such an insignificant repair/replacement that I did not expect such a big result, sounds like something everyone should do to their 4.0's...

Hopefully I have the same result on my 97... Needing to replace the valve cover gasket as it has a slight leak anyways... so figure I'll go ahead and change out the CCV as I'm sure it hasn't ever been done..

I didn't expect that much change...I also cleaned the inside of the cover up under the little cover plate they have covering the CCV and the outlet with brake cleaner couldn't remove the plate but sprayed the crap out of the openings and watched it run out it was kinda gummy in there but still not as bad as I have seen on other engines, and again the result is night and day...I know a lot of people do a little mod or something and say I feel more power or I now get 100 MPG's and I also know most of that is the "placebo effect" LOL...but this was a pretty big improvement that I did not expect...