Yes it could.

 

So I replaced the solenoid pack connector today and no change, I didn't think that would do it but it needed to be replaced. Since my erratic idle goes away when the solenoid pack is disconnected I decided to pull wires out of the connector one by one to see if I could narrow it down. With both wires from the trans temp sensor removed it idles fine but still dies when put in drive. With the power wire to the solenoid pack removed it idles fine and doesn't die in drive.
Even though the solenoids Ohm'ed out within spec I'm beginning to wonder if the solenoid pack is bad but on the other hand the ECM is grounding(activating)the torque converter solenoid as soon as the key is turned on, I confirmed that at the solenoid connector.
I think I'm going to call the place I bought the ECM from, maybe a tech might have some insight.

 

I checked a few more things today when I got home. I checked the four solenoid wires in reference to ground again but this time I checked from the male end of the C110 connector which goes to the ECM connector. Three of the four wires tested in the M ohm range but the P/O wire for solenoid 2 showed about 4 ohms. So a possible short between the C110 connector and the ECM connector?

 

The connection between the C110 and the PCM connector should all measure a very low resistance when using the PCM connector's respective pin that correlates to the same circuit's pin on C110. If you were measuring the male end of C110 in reference to ground and found the P/O wire is 4 ohms, you have a short to ground which will energize the solenoid whenever the PCM Power relay is energized (key in the Run position).

 

I started getting into the main harness today(what a PIA)and so far all looks good but I need to remove the fender well to get at the rest. Before I started I checked the solenoid wires continuity between the C110 connector and the ECM connector, the P/O wire has continuity with 6 other wires at the ECM connector...WTF? I have another 12 or 13 inches of harness to go through tomorrow, so we'll see whats goin on.

 

Was the C110 connector disconnected and solenoid end hooked up? I am following this per the Haynes chasiss electrical diagrams pages 12-54. The #1 solenoid red ties into 5 wires per a joint @pin 37 @ the pcm. Your reading continuity of all that .

 

I'm testing in between the C110 connector and the ECM connector with the connector not attached to the ECM. I already inspected the harness that goes to the solenoid pack. I'll find out exactly whats what tomorrow when I unravel the rest of the harness

 

Yes , that’s odd , the p/o has continuity with other wires .The p/o should not share that, curious to see wtf that problem is .I share your pain ,I have traced through the ecm wires .Have had both fender wells off and removed my ecm quite a few times .Earlier years I tried to get a schematic of the (inside )ecm to no avail.Ford protected I assume.
Getting codes on my 1985 is the reason I did away with its ecm. Being a manual it could easily happen,just wish my 92 was a manual,that ecm would be history ,especially with all these new fuel injection systems .Of course your in Cali ,big difference

 

So evidently there is two P/O wires in the C110 connector, I didn't see the one for the solenoid as it was in the middle of the connector and I assumed there would be only one P/O and of course I was testing the wrong one.
Anyway the P/O for the solenoid tested fine and since I have the entire main harness un-wrapped I physically checked all the wires from C110 connector to the ECM connector and all is good.
Ok so since I have back surgery next week then a schedule change at work when I go back my reliable daily driver for the last 11 years is gunna have to be mothballed, this actually the first time in 11 years this truck has ever let me down.
I'll just sum up what its doing and what I have done:

Problem: Code 629, stalling when put in drive and very erratic idle.

What I've done: Inspected and tested solenoid wires from trans to ECM, tested solenoids, replaced solenoid connector, replaced TPS as it tested bad, I had a spare VSS so I swapped out my old one and cleaned all connectors.
As you can see in the picture in this thread my ECM was fried so it was replaced and didn't fix the problem so it was replaced again then again for a total of three different units, last two were reman's.
Things I've discovered along the way: 1) The P/Y wire for TCC solenoid is activating(grounding)the solenoid ALL the time even with ignition off
2) Erratic idle problem goes away and engine runs smooth when solenoid pack is unplugged.

If anyone has any more suggestions that haven't been covered please share.
RLA2005 and Black XLT thanks for your help and suggestions!

 

For the heck of it I pulled the ECM out to check for burnt stuff , everything was ok. Looks like they replaced both of the troublesome capacitors and as you can see in the bottom of the pic they added a jumper wire to one of them, I'm assuming since I am having the same exact issue with three different ECM's that this isn't a problem. And for 570.00 they could have at least cleaned the board everything is covered in a white dust.

 

Will continue to research on your problem and wishing you the best with your back surgery.Let’s assume the ecm/ pcm are good ,,you stated the icm tested good and you replaced your distributor along with the tps . Example -I replaced my distributor last year (BRAND new- non Motorcraft )truck would not start after refueling -gas station ,(there was only 500 miles on this part).,towed it home ,culprit -brain distributor went bad ,Wtf only 500 miles., ,Prieviosly was running a msd ignition and was in the process of rebuilding it myself and (waiting on parts ) I could not get a new motorcraft and called performance distributors .After good words ( and many miles on this one) I am happy ,!and my idle is correct .(they replaced the 500 mile bad dist.)Shelf has two distributors ,
I do not like that picture of your ecm ,I would clean where the connector attaches to your ecm plug
TR

 

Thanks for the best wishes on the surgery, shouldn't be to bad.
I messed with it a bit this morning because the fact that the erratic idle is gone and it idles smoothly when the solenoid pack is unplugged has been bugging me.
Like I did last week I started pulling wires out of the C110 connector one at a time to see if I could narrow it down.
When the GRY/Red wire is out of the loop the erratic idle is gone and it idle smooth but it will die in reverse and drive. That wire is for the trans temp signal return and goes to the MLPS and the ECM. Since any shorts have been pretty much eliminated I'm guessing its the trans temp sensor or the MLPS.
I'll probably order a Motorcraft MLPS and mess with it after I recover.

 

Per my print ,Haynes 1992 and later :grey-red also ties into the map, tps sensors,egr valve position sensor ,hego sensor,air charge temp. sensor,mlps ,knock sensor,and the power steering pressure switch .Also the engine coolant temperature sensor.
There is a procedure for testing the MLPS .The MLPS tells the transmission what gear it’s in so it may act accordingly .or actually provides position input to the pcm ,so the transmission can be properly controlled by the pcm. Electronics GO Figure lol.

 

Update.....I got a replacement ECM(number 3) from AutoECMs and that fixed the stalling in drive and code 629 problem. So now I'm back to where I was two months ago with the erratic idle/stalling/missing problem and code 212, the code 212 has been lingering on and off for 2+ years so I'm not even sure that is related to my problem, I've pretty much checked for shorts around the shielding/foil and all is good. My fuel pressure was low so I replaced the fuel pump and the numbers didn't change at all still around 26psi with vac at regulator connected and about 36psi with vac removed from regulator and about 26psi when reved to about 1500 rpm, regulator vac line is dry and filter was changed about 3 months ago.
Anyway, just thought I'd update.
Have a good Labor Day!

 

Great, the other problem can be solved in time , this reassures me that the computer was the culprit ,as the research I did in here and FSB ,the computer swap fixed that stalling on every post.Of course throwing money in parts at this gets costly.I am bewildered that it took 3 times and wonder if your other problem is the same,the Ecm/pcm .Best way is to trouble shoot like before .
Years back I had a problem at 1800-2100rpms the truck would surge ,culprit was actually my instrument cluster .All the research / troubleshooting I did was at a dead end and the help of a experienced Ford tech ,problem solved !(Break out box and graphs lol).(Junk yard instrument cluster )
I thought I actually get the BIG problems .Year ago again I could go to start this beast and it would not start ,perhaps like it was locked up ,Wth,again? Problem ,after much time and troubleshooting- I had installed a super chip in 2003-2004 and in near high humid/damp conditions this occured. BUT only certain days .I installed this because the transmission shifted better ,it actually up the pressure with this chip .Chip has been removed ! Problem gone. I think I have traced over every computer wire and others in this Bronco .There’s been other problems /idle / heat-plug wire break down / fuel injectors / alternator/just to name a few lol
Also I have seen certain copy cat parts cause problems Electrical/electronic .Glad you posted an update makes us researchers happy Good luck Happy Labor Day!