So your saying the test light should not illuminate with the key on ,engine off,test light hooked to + battery terminal and probe in ground wire at injector clip?

EDIT: To clarify, If the injector electrical connector is Disconnected & your probing it's load/TN lead/contact, going back to the computer, (this will be the TAN color lead for the #1 injector, Not the Red 12 volt B+ feed wire), the test lamp shouldn't light up, unless your cranking the engine & the computer ground switches the TN injector lead, or if it does light up, the ground switching driver is shorted, or it's TN wire feed from the injector wiring harness is damaged & is shorted to ground some where in it's run. If the injector were constantly grounded, it would be constantly open/on & squirting fuel.

Further, if the #1 fuel injector electrical connector is Connected & your Back Probing the TAN wire at KOEO, it'll have 12 volt B+ to it through the injector solenoid winding.
If the injector electrical connector is Disconnected, the TAN wire Won't have 12 volt B+ on it, Only the Red wire will have 12volts B+ on it at KOEO.

I will try to clarify what Pawpaw was saying.

There will be power, B+, battery voltage, to one wire on the fuel injector whenever the key is in the ON position.
The computer controls the other wire, which would connect to the other side of the internal winding in the injector. The injector operates like a solenoid, pulling the valve open when the ground is applied, voltage flows, and makes the winding into an electromagnet. When the ground is taken away, there will STILL be 12v on both connectors on the injector. The voltage will be coming in on the B+ wire, going through the injector coil, out the other side, and all the way to the computer terminal. It will NOT flow, the same as you have voltage at your wall outlets, but the current does not flow until you connect something to use the electricity. In this case it is as if the B+ wire comes in and goes out all the way to the computer, and just sits there until the computer completes the circuit allowing electricity to flow. Again, both wires should be 'hot', and the one leading to the computer should be hot until it gets grounded, and then the voltage will tend to approach ground for a fraction of a second.
A mo bettah test might be to connect a test light to the computer injector terminal with one wire, the other wire from the test light connected to the + terminal of the battery. Cranking the engine, the light should flicker as the computer provides ground to complete the circuit, allow current to flow, and light the light. Beware of overdrawing the grounding circuit controlling transistor. I do NOT know amp limits, so don't use a big bulb?
tom

My experience with a misfire turned out to be a Crack in the head between the valves. Common on these engines. Almost likely if you have any decent amount of miles there are some cracks forming. One day they just let go. The head shop said they do 10 of these a week for cracks.

After chasing the misfire issue for over 6 months one day it finally happened and she was blowing white SMOKE. STILL showed good on compression until that day. It finally let go at a Crack near the water jacket. I'd never have found the cracks otherwise.

1 thing however that became more obvious looking back, as the cracks got bigger I noticed more valve chatter.

One1, this is the first I've heard of crack problems, and I have been active in EMT 3.0 for ~5-6 years, and Ford products for 50.
I just have not hear one whiff of an endemic problem. As they call it, this report is anecdotal, FWIW. I wonder if the cylinder head shop/mechanic was making stuff up as he went, sometimes done to mollify an unhappy customer so they don't feel so bad about their $1k going out the door. I have no idea where to find out. Consumer Reports? But, all they do is test new cars, right?
Engine Rebuilder News, if there was such a place? Availability of re-man heads? Do you have to wait? Or are they 'on the shelf' ready to go because of demand? I do not know.
tom

Well there's gotta be a first time for learning everything. Here's the pics of my head. It looked just like the other 4 sitting there in front of me waiting to be done.

Dont know if this good news or not haha

Has this 2.3L ever been seriously over heated? Or was the coolant allowed to be in the system too long, such that the cooling system is all coated up with deposits, such that it's thermal conduction/heat removing abilities have been diminished?

Never overheated..but to be completely honest ive never changed the coolant or flushed the radiator for that matter,which is quite embarrassing.

OK, good feedback, not seriously over heated, just the cooling system hasn't had a regular scheduled maintenance coolant change history.
When you get this problem squared away, try & discipline yourself to perform the owner manual specified scheduled maintenance call outs, with parts & fluids that say in writing they meet or exceed Fords specifications, as regular scheduled maintenance can help our rides run real good & last a looooong time & in the end not cost too much!!!!
Let us know how it goes.

I've since sold my Ranger but I believe that hose ran between the runners of the intake manifold and over to the purge solenoid. But I'm not 100% sure of that.