I recently purchased a 1994 ford ranger I knew there was a couple issues when I bought it that I had ended up repairing like installing a new radiator but another issue I noticed is that the positive black and orange wire coming from the alternator connecting to the drives inside fender near the fuse box had a smaller gauge wire spliced to it and had appeared to have melted. The truck ran fine and had no check engine light on when i bought it but after I brought it come I replaced and the wire with a larger gauge wire and drove it for 2 days until I noticed my voltage meter in the truck was reading high like around 16 volts. Then the check engine light came on it gave me codes 224 and 223 also my ac compressor and randomly started constantly trying to turn on and engage resulting in a clicking noise about every 30-45 seconds I shut the truck off pulled the fuse for the ac and put it back in and it seemed to fix that problem. Also when check the codes again it no longer showed code 223 just 224. I used a multimeter to check how much power the battery had and it had 12.5 and 14.5 when the truck was running the alternator also showed it was sending 14.6 to which i assume is the starter relay on the drivers side fender I checked the grounds for my alternator cab and chassis all good so after looking online I had seen that 224 is a ignition coil circuit based code but I looked up all the symntoms of a bad ignition coil or bad ignition module and I dont really fit any of them. The truck runs good it has plenty of power and the truck runs with perfect voltage when the alternator is disconnected to I guessed it was the voltage regulator on the alternator (which was brand new) so i got another brand new alternator put it in and i have the same issue. Im stuck and lost everything meters that its sending the correct voltage but the gauge inside says its getting to much and on my way back from work on wednesday the meter actually started to touch the red portion of the gauge and then the truck would have a issue running when it touched it turning my headlights on seemed to draw enough power to get me home. need help

 

Welcome to the forum

I don't think anyone has the code list memorized so its good to post the definitions for the codes, also double checks if you are using correct definitions, lol
223 (M) Dual Plug (DPI), SPOUT or IDM circuit fault – Ignition Systems
224 (M) Failure in ignition coil primary circuit – Ignition Systems

Both spark plugs in each cylinder fire at the same time, no alternating
So if one coil pack has a problem you rarely notice it
With engine idling use rubber handled pliers and unplug one coil packs 3 wire connector
Engine should stay running with NO misfires
Plug it back in and test unplug the other coil pack
This tests both coil packs and the 4 spark plugs on each coil pack


The dash volt gauge is just hooked up to general 12v wiring in the vehicle, no connection to the alternator specifically

Key off battery voltage should be 12.3v to 12.8v, this is after vehicle has sat for at least 4 to 8 hours, engine off
12.8v-13v is a newer battery
12.5v is a 3 year old battery
12.3v is a 5/6 year old battery, time to shop for battery sales

Engine running
Battery voltage should be 13.5v to 14.8v, never 15v or higher, never under 13.5volts
If you do not shut off the engine when you get home and test battery voltage after driving for at least 20min you should see it at 13.8v to 14.2v
Just after using the starter motor the battery is drained, so alternator puts out a higher voltage, 14.5v+, this is normal
Once battery is charged back up, after driving a bit, alternator(voltage regulator) will lower the voltage to under 14.2v usually

 

If not the alternator where would this excess voltage be coming from ?

 

What high voltage?
You said battery showed 14.5v engine running

Dash gauge would also be 14.5v, if it said 16v then gauge is bad

What ever it shows at the battery terminals will be the voltage in the whole vehicle
If engine is off and battery shows 12.5volts then the whole vehicle has 12.5v
If battery shows 14.5v engine running then whole vehicle is at 14.5v
If anything shows higher then its broken.................or your connected to ignition coil, 20,000volts, lol

 

when running everything meters at 14.5 just like it should but the gauge shows 16-17 if i disconnect the alternator it then shows the correct voltage

 

If you disconnect alternator then it should show 12.5volts, not 14.5v
So if it shows 14.5v, then the gauge is off by 2volts

 

I did the test you recommended by removing the three wire plug on the coils while the motor was running and the first one the engine did idle rough and bad after removing the second one had no issues. So i replaced the one i suspected to be bad and did the test again and got the same results. Should I be looking at the ICM now ?

 

You replaced the coil that caused the rough running?

Yes, on a 1994 the ICM(ignition control module) runs both coil packs, so next step
Also give the ICM wires a good look, after 30 years they can get brittle

ICM needs a good engine ground which is done by the 3 screws/bolts holding it to the lower intake, these can get rusted out, so replace or clean them up
New ICM should come with heat sink "goo", be sure to put this on the back of ICM when installing it

 

yes when I removed the three wire connecter on the first coilpack the engine ran rough, so I replaced it with a new one and did the test again and it still ran rough.

I will be looking at the ICM wires and looking to replace it soon and get back to you.

 

If you pull the 3 wire connector on one coil pack and engine runs rough then you replace the OTHER coil pack, the one that was connected and running the engine at that time

 

I did that backwards and replaced the good one with a new one but I took the other good one because the engine didnt run rough when it was unplugged and swapped it with the actual bad one and it still runs rough when the brand new one is unplugged

 

Brand new one should be plugged in, and that's what the engine is running on
Then unplug new one and plug in the "other" good one so its now running the engine

 

I went ahead and replaced both with brand new coils still have the same results with the test you suggestion thank you by the way. I then decided to test it by just pulling the plugs off the coils and see which ones were working. I discovered that 2 of the spark plug wires are not getting spark. I’m guessing my next step would be either replacing the spark plug wires,spark plugs or the ICM.

 

Each coil pack only has 2 coils inside, each coil sparks 2 spark plugs wired in series
They are in these pairs on either coil pack
1/4
2/3

So if the 2 spark plug wires with no spark share the same coil, and the coil pack is new, then its most likely the ICM is not grounding that 1 coil in the pack
So which spark plug wires didn't have spark?