Need Help 04 explorer making chattering noise/idle rough

[mooreg285]

I need some opinions my 04 exp 4.0 xlt is idling very rough even more so when it is in drive not so bad when it is in N or P I replaced the spark plugs and this fixed it .... days later I replaced the 02 sensor bank 1 s2 and it was still fine now it is running horrible when I go to start it, it'll start fine rims shoot up to 1.5 then almost bottom out making the car almost die then will balance back out right under 1 and become like there is a miss in it rough. Then it will start to what sounds like a valve chatter or spark knock but will go away when rims are increased so I took all wires off made sure all had good connection and they did. I am lost I am going to try taking all plugs back out to make sure no gunk got on them while installing causing a miss in fire does anyone have any idea why it would only idle horribly but when rpms are up its ok

 

[Number4]

Chattering is usually a sign of something wrong with the timing.
If it's to the point that the engine isn't running right, then the timing may be off. The next step is engine failure.
After the engines sat for a while (over night) pull the valve covers and see if the chains are loose. Or see if the guides are busted.