Sup guys.
This problem is getting very bad!
Let me state my problem first. (this is my g/f eclipse): all stock no mods.

Problem:
ok, when I start the car, it will start right up, but then if I don't give it some gas, it will die right away. so I have to give it some gas for a few mins and it will stay up after warm up. (happen on day time)
Then I can drive the car around and shut it off and on, and so on. it's fine.
Then at nite after the whole car is completely cold down. I start the car again, it will start right up again, but then I have to give it gas again till it warms up.
Sometimes after a while, it won't even stay up, and I have to drive around on Highway for a while before it will stay on.

Changed:
I put new spark wires 6 months ago.
I put new spark plugs 6 months ago.
I put a used alterator from a working eclipse about 1 week ago after this problem started. (problem been around for 2 weeks since winter/weather start cold)

OK, can someone please tell me what's up?
Can it be the alterator is still bad? or battery is bad?

What I am thinking is this:
-just changed a working alterator, should work.
-new spark plugs and wires, so that won't be it.
-can it be the coil pack for the wires?
-can it be the starter? but it start right up, just won't stay up...
-can it be the battery? but if I drive on highway for awhile, it's fine...
-can it be the fuel pump, so no fuel is getting there???

What the problem seem like is that, whenever the engine or weather is cold, it won't stay up.... ???

PLEASE HELP ME OUT!
It's been like this for 2 weeks... so horrible!
Any help is greatly apprecaited!
Gil:bowdown