94 ranger 4.0 4wd RPM problems. Ideas?

[awesomebilly]

Hello everyone!
So here is my problem. I Hope someone has a clue.
I bought my truck about 4 years ago and I've never really got to drive it (its been broke down off and on)
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94 Ford Ranger 4.0 FWD. Stick. 90k miles.

RPM's drop to ZERO, doesn't stall, Right now RPM is stuck at zero. The RPM shoots between 1.5 and zero, when it does move. While I'm driving the truck will run fine, then randomly lose all power-zero-rpm, I can maintain my speed with max pedal but can't accelerate. If I turn the key off then back on while driving I can get power for a few seconds, then back to zero.
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In the past I replaced the MAF and TPS (quite a few times) and it fixed the problems (for a few hundred miles).
Its been in and out of the shops. They replaced the catalytic converter, Fuel pump, Gas lines, Fuel filter, The Air intake Manifold.
Its been over a $1,000 dollars. I'm lost at what to do now.
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Few things I did today.
Today I took the throttle body and cleaned the heck out of it.
Cleaned the MAF TBS
Took off EDIS and cleaned it.
One thing I noticed was under the DIS (I believe that's what its called, The spark plug wire connector area) It has a solenoid that looks broken, wire is hanging off.
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Thanks again if anyone has a clue.

My code reader extracted a code 411 in the "Key On Engine Running" portion of the test. Code 411 is described as "Cannot control RPM during KOER low RPM check".

Also 226, 136.

 

[awesomebilly]

Checked today, Changed plugs and wires.
Did KoEo and KoER

KoEo
157 MAF volt too low (whats this mean? bad MAF or something else?)

212 Loss of ignition diagnostic monitor {IDM} Signal - short to ground in spark output {spout} Circuit.

232 Electronic Distributorless ignition system {EDIS} problem - Ignition Diagnostic Monitor {IDM} Signal not received.

KoEr
136
Heated Exhaust gas Oxygen {HEGO} Sensor - Voltage signal no switching during engine run self - test. Indicates "lean" {Bank #2}

 

[Nhaz]

I would start going over the wiring on that truck and start checking for bad grounds or just bad wires. Like everywhere.

 

[awesomebilly]

like removing the wire harness? And tearing off the plastic casing and following it like that?