Engine issue:
low hp, skipping, backfiring at speed and acceleration,
Installed FF EMULATOR, GAINED ALLOT OF HP BACK, when engine is cold or cool, runs ok with a once in a while miss at idle, camshaft sensor, plugs, wires, all changed, looks like crankshaft sensor been also changed, cleaned mass air flow sensor with proper cleaner, still misses and backfires under acceleration.

#2 transmission slips a little going into reverse, have to manually shift as it automatically shifts @ 2200 rpm, ever gear,

Any Help Appreciated

 

Welcome to the forum

Can you or have you done a compression test, all spark plugs removed, DRY test, Cold engine
What that does is to take a compression issue off the table so you can look at spark or fuel delivery as the problem
If there is a compression problem then you will waste alot of time and money on non-fixes

So always best to do compression test first, as its a mechanical function no "grey" area, either OK or its not

You can do a Vacuum test, disconnect coil pack, should see about 2" of steady vacuum when cranking engine over, and NO bouncing of the needle
Then engine running Vacuum should be 17-20 inches if compression is OK and NO bouncing


Delay going into Reverse means fluid pressure in transmission is low
Forward requires 120psi
Reverse 160psi <<< this is why slow engagement or loss of Reverse is often the first sign of pressure issues in automatics

There are pressure test ports on the sides of automatics to see where pressure is being lost
Trans shops can test that
Its more often that not that the valve body has seals and gasket leaks causing lost pressure so this can be fixed without dropping transmission out

You have a 4R44E automatic in a 2000 3.0l Ranger
These are the same as the 4R55E, 5R44E and 5R55E as far as trouble shooting, so what applies to one applies to the others, when looking up symptoms

If transmission is over 250k miles it might be time for a rebuild vs just valve body work, but valve body is not a waste of money since you would need that for a rebuild in any case

 

#1 - To be clear.. did the condition exist before all these parts were changed? Verify spark plug wire firing order?