The air intake temp sensor can cause your pcm to dump fuel. If it has come loose and is hanging in the engine bay it will be "sampling" the temp of the bay and not the incoming air stream.
Another thing to check is your spark. If your coil is going out or your wires are arcing then the fuel is not going to burn properly. This also accounts for stumbling and backfire issues.
You sound like you know what your doing but make sure you have the right plugs and that they are gapped right.
I don't know how you checked the fuel pressure but I would also swap the fuel filter. This is usually a cause of fuel starvation but it's a cheap replacement.
