Intermittent 1221 and 1222 code

[White535Mtl]

It has been occuring for quite some time now. But now the 1221 code pops up.

Let me start from the beginning all over again.
I've been having 1222 codes flashing with the car stalling under rain, and humid temperatures. It would occur for a few days, rough idling, no power unless at WOT, and it seems to accentuate when car is inclined.

What worries me now is that it recently dropped below 0c and the lady just popped up code 1221, which I hadn't seen yet.
No erratic behavior, YET. It just happened as I turned the corner to get to my house.

I brought it to my mechanic, and diagnosed that I had low fuel pressure. He changed the fuel filter and it helped somewhat the fuel pressure. He says that it's still low.

And I changed the Crank position sensor the first week I got the car.

Any pointers? O2 sensor? fuel pump?

[Gdub]

I had the same symptoms and codes u got and had low fuel pressure also. I took a look at my fuel pump and it had a large crack in the metal casing. Replaced the pump and the car is running great. I would post a pic of the crack in my old pump but i dont have a camera right now.