Code NUMBERS would be nice..
The sensors stating that they are lean (VERY UNREAL to have BOTH go bad at the same time..) could be just that... The sensors could simply be stating what they truly are seeing.. a lean condition. If you have something creating a lean, the sensors will simply tell you what they see.
Look for other problems, not TWO bad sensors at once. I would look for any air leaks after the MAF (TB gasket, UIM/LIM gaskets, EGR gaskets, vacuum hoses cracked, brittle, broken, or missing.
Spray carb starter spray in to different areas, and see if the engine sputters, or stalls. If it did, then the spray made it in to the engine and caused that to happen. You found your cluprit area. (avoid letting the spray in to the air filter area.. you don't wanna create false results!!!)
Anyway.
Look for loose hoses, EGR vacuum hoses on top, etc...
Ray