Running lean...why?

[TheDarkKnightt]

My XC just threw a check engine light. Only the second time since I've had the car, period.

Say "lean on bank one" and it's idling rough.
I passed the emmissions test the other day, and it just started this this morning while I was idling at a red light.

I cleaned the throttle body when I did the PCV system.

Stopped up or leaking injector? Another bad fuel pressure sensor? Badly seated O-rings? Badly seated intake manifold gasket? Stretched timing belt?

Suggestions appreciated.

[Scopeman]

Could be a vacuum leak anywhere. Plugged fuel filter, does VIDA report fuel pressure? Could be one plugged injector. I have used WitchHunter Performance for injector cleaning and highly recommend them! Was the code read by VIDA? If not, VIDA may provide more info.

[vtl]

Unplug wires from VVT solenoids, is it getting better?