1989 5.2 b150 black smoke

Hey all, any of you have any knowledge on 5.2 throttle bodies? This is on my work truck that has been very dependable for years until now and it's needed greatly for or work.
Mine won't start unless I floor it and then it's a huge cloud of black smoke and stays that way after it starts.
As I crank it over watching the throttle body it is dumping way to much fuel during the cranking.
I have tried a new MAP sensor but no change.
If anyone has an answer for this please pass it on.
Thanks.

When you crank engine, can you see each injector pulse back and forth? or does one injector just seem to not turn on and off while cranking? I ask because I've heard of o-ring failure that lets fuel pour around injector, instead of going through it.

Throttle blades below the two injectors are almost closed but the injectors seem to want to dump a 1/4 mile pass into the engine.
I just did another look and got a face full of atomized fuel, blaaayuk.lol
The injectors seem to be doing there job of spraying equally but just too much.
This was a sudden thing that happened with the engine no warning after a month of rain but nice and dry now.

Have you done the on-off-on-off-on thing with the key yet to check trouble codes?

I don't know how many times to do the on off code check.

Super rich is often ECT.
Check codes and check the sensor up near the thermostat.

Do you have the steps for checking code with key?
Thanks for the tips on the coolant sensor.

Put key in ignition, then turn it to on, then to off, then to on, then to off, then back to on, all in like 4 seconds total time, then count flashes of eng lamp.

3 times off and on, last time leave it on. get a pen and write the flashes. all of them are 2 digit codes. (if you miss one, just redo the test, after the codes are done flashing. it doesnt erase itself after you run the test) the squirts should be so tiny, as to be almost invisible when cranking and at idle. and you should easily be able to see the pulses moving from left to right sides. if it's anything more than just a tiny wisp of fuel something is wrong with the injector, or the signal being sent to it.

Thanks all for the tips, I got it going.
I had changed out the MAP sensor earlier in the day with no change, unless it takes MAP sensors a while to get going.
So under the advice of RodStRace I checked out the ECT sensor,
Took the plug off cleaned it up and reinstalled.
Truck ran much smoother but still very smokey, let it get up to op temp.
No smoke at idle only on revving engine, took truck for drive on the Hiway and it cleared up as I drove.
Runs great, starts fast and clean, Thanks again for the suggestions.

Throttle position sensor.

had a similar problem on 89 B series 5.2, was O2 sensor,rough choppy idle,would almost die,ran hot,miss with load....