RPM very limited, can't get over 2000 rpm
 

My 01 Ranger 4.0 is idling really rough and when I drive it can't get over 2000 rpms. I ran my code reader and it gave me a code P0113. It said that the Intake Air Temperature sensor was faulty. I changed out the Mass Air Flow Sensor but no change. I'm thinking it's all fuel related.

I just got back from a seven month deployment and it had sat in the rot lot the whole time. It's been running fine for the last two months and then popped up all of a sudden. I ran some fuel injector cleaner two tanks ago. I'm thinking it busted loose the grime and gum that the bad gas left in the tank from the deployment. I've changed the fuel filter and put some fuel system cleaner in it but it isn't changing much.

My fear is that it's a fuel injector issue, which I aint a good enough mechanic to tackle that problem.

Any Ideas?

Yes, could be limited fuel supply but also reads like clogged exhaust, collapsed Cat or muffler.

It can happen suddenly, have someone rev engine while you feel the tail pipe flow, you can usually tell if flow isn't increasing with RPMs.

Injector issue wouldn't fit description.
Low fuel pressure would, you can rent or "borrow" tester from auto parts stores.
'01 should show 65psi when idling, raise RPM and see if it is dropping.
It should also hold pressure when engine is off, should stay above 50psi for a few months.

Pull out a few spark plugs and see if they can tell you anything.
Google: spark plug condition