Let's back up a step or two, and get some more detail on the symptoms and what you may have done to this point to address those. I'm guessing (hoping) that all the item on your list have already been checked out. What has been done so far?
Also, you need to do some organized troubleshooting, instead of chasing possibilities from system to system.
If you have some notion that you have a fuel pump problem, test the fuel pressure. You should be able to read a constant 11-13 PSIG under all operating conditions. If that is a problem, you'll need to repair it. If not, you can take it off your list of possibilities.
Another item to check is the ignition system. Once you verify a reliable ignition system, you can eliminate that from the list. Test the resistance of the ignition wires, or replace them. Inspect the distributor cap, rotor, and coil for moisture, carbon streaks, pitted contacts, or physical damage. Remove the spark plugs and inspect the electrodes, gap, and insulators for damage, or just install new ones. No "designer" plugs - just the regular old, side electrode, copper cored plugs. While you're there, check the connectors at the distributor, just for grins.
Inspect all the vacuum hoses, including the brake booster hose and PCV system. Clean or replace the PCV valve while you're there. Another vacuum-related item to check is the EGR valve and control system. A lot of mysterious poor idle and low RPM performance problems can be traced to a leaking EGR or faulty EGR control system. Of course, you'll want to check for obvious gasket problems at the IAC, throttle body, and intake. A quick idle vacuum reading might be useful in determining the likelihood of a vacuum or EGR problem.
Once that's done, you should clean the throttle body, throttle plates, and remove, clean, and lubricate the IAC. Set the minimum air positrion and TPS when you do.
By then, you should have a good idea of the problem(s), or at least have done a lot of routine, scheduled maintenance that will eliminate a lot of possibilities.
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"Everything should be made as simple as possible, and not one step simpler."