00 4runner stalling at idle!

This 4runner is driving me nuts! So the symptoms are:

1) Stalling at idle in "drive" at operating temperature.
2) idle fluctuating in park from 900-approx 550-600. Sometimes stalls!

The truck runs and drives just fine. Does not seem like it is misfiring or underpowered. Only problem is during its idle. The engine stalls after about 3-5 minutes of idling, sometimes sooner.

So far I've replaced the:
IACV
PCV valve
Spark plugs
Air filter

I cleaned:
MAF sensor
Throttle bodies

Everything looks as if it is in good shape. The IACV valve wasn't dirty and PCV valve rattled just fine..

No check engine light on. The most recent light was the P0441. I changed the gas cap and deleted the light, it hasn't came back in about 500 miles.

Any ideas?