1992 240sx No Idle/Dying while in Neutral

[adam s]

If I can get any help at all it would be amazing.

I have a 1992 240sx LE
160K

Here's whats happening:

Starting:
1. When ever I go to start the car, it cranks for about 20-30 seconds.

2. As soon as it starts getting gas, I have to press on the accelerator to keep it from dying again.

3. If I take my foot off the gas, it will die.

4. Hence no Idle.


Driving:
1. Car drives fine, maybe a little rough, however, as soon as I put it in neutral for a stop, coasting, w/e, it will die unless I force it to "idle" by revving the engine.

Some of the problems I noticed when i began to diagnose, and a little history:

1. Replaced a misfiring injector about a month before the problem.

2. Replacing corroded battery connectors as we speak.

3. Spark plug wires are 3 month old NGK blues (I know, I know...)

4. Spark plugs are black black.

5. Valve cover gasket and spark plug gaskets were replaced 5-6 months ago to fix oily exhaust smoke.

Thats all I know, when I got the car about 7 months ago it pretty much ran fine except valve cover.

Only things that came to mind for me were:
Alternator?
Battery? (no idea how old)
MAF?
IAC?

Any help would be greatly appreciated.