Ok, the only thing coming off the negative terminal is a probably 4 gauge wire going to the block. There is no green/black wire nor a small wire going to the body. On the ground going to the block, there is an open piece of the wire with a metal connector that I assume was supposed to be tied to the frame. I've seen it in a few other cars. It's just freely floating right now but I will bolt it to something or run a jumper wire.

So I checked the wires coming off the splice that goes to the battery terminal hookup clamp that is unconnected; one is black with a green stripe and one is black with a white stripe. I hooked them up to the negative terminal. There is also a point on the frame where a green/black wire connect to the body by the battery.

Going for a test drive, brb

No, the thread hijack is helping.

 

It appears that the ECM in the truck is for an '84 lincoln.
You also wrote "So I pulled the ECM and it's not the same as what's in your pictures."
This concerns me.

There's probably too much of a mis-match in the lincoln EEC to work correctly EVEN IF the wiring problems in the truck are corrected.

My issues were noticible in park/neutral as well as driving.
You've got a monster motor under your hood and it may "mask" some of the symptoms my lil' 300 was having.

Bob

 

b0bd0d,
You did not say anything about a body ground. There got to be a large 10GA wire running from the NEG post of the battery to a body ground point where the black wire with a green stripe and the black wire with a white stripe are all connected together.

The body ground and G102:


The black wire with a green stripe grounded at G102:

/

 

Ok, so I ran a body ground and that really didn't make difference.
I put a vacuum gauge on the engine and it's about 21 in. Hg. The needle flutters every so often while at idle and you can hear a little popping sound when it does. I assume that's a misfire or a stuck valve? I'm going to test the wires, the spark, the plugs, then maybe the injectors. Is there anything else I should look at?

@bob
No, the plastic housing had that number stamped on the back of the plastic ECM housing. The sticker that is on the front had a 1989 F250 460 5-spd part number. I may have misread it, as I just plugged the numbers I wrote down into eBay/Google.

 

Gotcha' on the housing numbers etc......

I just spent some more "quality" time with my truck this morning.
I've come to the conclusion that MY truck has a small air leak in the fuel line(s), I think at the rubber O ring in the fuel pressure regulator.

I was doing a little pondering as to why this may have happened, I thought.....humm.......why would a rubber O ring leak ?????
Well, think about it.......many years ago, when our trucks were "new", ethanol/gas mixture was relatively new............promises were made about how the "new fuel" wouldn't harm our vehicles........yeah, right.

Hummmm............perhaps what we're experiencing right now are the effects of ethanol drying out all of those little O rings in the fuel system (i.e. fuel filter, injector sealing rings etc.) causing air to enter in the fuel lines.

The stumble could be from the delay the of computer trying to increase the injector pulse rate to compensate for a lean condition which could be due to air in the fuel lines.

That's just a little guess/huntch I have as to why our trucks aren't running like "showroom new".

Something to think about,

Bob

 

Air can not get into the fuel lines. They have pressure in them and not vacuum. If the seals were bad the fuel lines and seals would leak fuel out.

 

Just for grins........

Try running a temporary heavy guage ground wire from an alternator mounting bolt to the negative post on the battery or to the fender ground and see if the missing disappears.

Just a hunch,

Bob

 

I just wanted to come back and post what I found and how I believe the problem was solved. I hate finding a thread with my exact problem but no solution or hints of what occurred next.


TL;DR:
Had error code 34 in memory and when doing KOEO test. It was a bad EVP sensor from advance auto parts with wrong resistance when closed/open. Computer got confused and changed the mixture. Still stuttering but looks like a spark/ignition issue in the distributor cap. Error 34 fixed; I think. Scan tomorrow.

Long version:
The new EVP I got from advance auto parts was not working as it should. When the plunger was fully extended, the new EVP read about 3500 ohms. The haynes manual says it should be 5000 ohms. When the plunger was fully pushed in, it read about 900 ohms. Haynes manual says 100 ohms.

I went to the junkyard and tested several Ford EVP sensors. Most were around 4100 - 4300 ohms fully extended and around 100 ohms fully pushed in. I got a good used one and swapped it in. Truck has been running much better and I will check for codes soon.

I think the new EVP sensor resistance was not high enough and the computer was thinking it was open when it wasn't. This was making it adjust the fuel/air mix to account for a leaking EGR when in fact there was no leak and making it run like ****. The computer might also think the EGR was more open when it wasn't. The stuttering and stuff is still occurring but that appears to be a spark/ignition issue in the distributor cap. I think I have the code 34 fixed and will scan codes tomorrow.

 

If you have a vacuum leak or a vacuum leak in the cannister it'll cause a stumble too.

The vacuum system with the cannister (coffee can) has to be functioning as designed (stock) and can't be depleted of vacuum, otherwise you'll get a lean stumble till the computer can re-adjust itself.
That includes the correct sized vacuum lines, routing, and any vacuum connectors that might be used to keep the "coffee can" from being depleted of vacuum.

This is something else you need to check and verify.

Been there and did that last weekend,

Bob

P.S. I think the new parts you got from Advanced were probably fine and will function correctly AFTER you check and get the vacuum system working as designed.

 

One of the first things I did was check for vacuum leaks. I also got a vacuum gauge and checked intake manifold vacuum. It was within spec.

When I changed the new advance sensor with the one from a junker, the truck ran a lot better. I'm pretty sure the resistance values on the new sensor were not correct. The 3500 ohm resistance at EGR close was not dropping enough voltage to indicate closed to the computer. The max voltage drop allowed is 0.67 volts for closed position and the new sensor was dropping almost 0.9 volts. In addition, changing the sensor removed the error code during the KOEO test. It is still in memory but I will remove the codes and see if it comes back.

The number 2 wire is actually one of the shortest. I swapped wires out and it didn't change anything.

As I mentioned, I checked for spark by using a spark tester connected to ground. I ran the test and #2 cylinder is misfiring. During reading I came across this page: spout. So I disconnected the SPOUT connector and reran the test. There were no misfires and the spark looked strong. I reconnected the SPOUT connector and the misfire reappeared.

It looks like either the PIP sensor is not giving a strong enough signal to the ECU or the ICM is not sending enough to fire the coil. I'm not sure why it would only happen on one cylinder though. I think I need to change the distributor cap, perhaps the connector for #2 plug is out of tolerance.