2001 Explorer bad miss at idle

[chopmini]

I have a 2000 explorer sport with the 4.0. It was running real bad so I did a full tuneup (plugs, wires, fuel filter, pcv, coil, air filter). It ran better, but not great. It had a miss at idle when cold. Once warmed up, you didn't notice it as much. So i replaced the temp sensors, which involved removing the plenum. Once all done, it was good. A couple of days went by and the miss came back. I hooked it up to my scanner and got some weird readings.
First off, I had 9 codes. Lean bank 1 and 2, multiple missfire, and missfire on each cylinder. I viewed the PIDs and got even a bit more confused.
At idle STFTRM1 and 2 are maxed at 42.2%, and LTFTRM1 and 2 is 25%. Oxygen sensors were also wierd. S11 was at .025, S21 was at .030, and S22 is 1.275
At 2500rpm, STFTRM1 and 2 ranged from -9.4 to 8.6. LTFTRM1 and 2 got down to 18.8, but I was only holding rpm for 15-20 seconds. The O2 sensors were a bit off still too. S11 ranged .040-.730, S12 ranged .050-.670, S22 stayed at 1.275.

As far as the FTRM goes, I am pretty sure it is a vacuum leak. Since it is dropping so far at a higher rpm. I have sprayed around with some carb cleaner to try to find it, but no luck. I even pulled the plenum back off and double checked all that again. Still the same after that too.
Oxygen sensors are still confusing me a bit.
Anybody have any input on the oxygen sensors? how about the vacuum leak?
Anything would be great.
Thanks

 

[rb142]

Definitely an air leak. Probably intake manifold gaskets or the inlet tube. It's pulling in a lot of extra air somewhere.