Hey,
The person that solves my problem , I will consider a genius.
Ford F-150, 5.0, auto, 4x4, 1996. Check engine light has been on
for a year come June. The code is 1351 (ignition diagnostic monitor)
Before your start coming up with try this and try that, well I have:

1)A brand new Ford cpm and ignition mod. have been installed,
2)A new distributor and new coil have been tried.
3)Fuses have been checked.
4) Relays have been checked.
5) Ignition switch has been tested.
6) Alternator has been checked for shorts.
7) All wiring between computer, ignition mod and dizzy and coil have been un-wrapped and run down.

It doesn't seem to be the 22k resistor.

The truck has been in three major garages.

When the light came on the truck had quit running and wouldn't start so the tech. at the garage installed a new ignition mod.
(an aftermarket brand).It started and ran but never could get the light off, so we ordered the ignition mod from Ford.
Still had the light.
Installed new Ford computer. Light again.

The truck quit on me again. I worked on it myself. Found three naked wires coming out of the tps (throttle position sensor).
I installed a new one. The truck has run great for going on one year now with black tape over the light. Sure it will erase but it comes back.
They tell me at Ford and at the parts stores there is only one ignition module for it and that I have the right one.
One time, before this last garage, one garage installed a ign mod that was black in color and it ran the longest without a light.

Oh ya,I had problems before this last episode I haven't told you about.
When it quit last,the Ford parts man said the black mod. was wrong and it was for a six cyl. So we supposedly got the right one which is gray. Could it actually take the black one even though I run a 302 (5.0)

What I actually told you is the last part of the problems. I made a long story short.
I'm looking for the miracle. Can you help? Any ideas?
Thanks,
Just Jack.

 

I remember the older EECIV computer units always gave you some pulses at the begining of extracting codes to tell you what computer you have. I think it was two pulses for a 4 cylinder, 3 for a six and 4 for an 8 cylinder. Is it possible along the way somebody installed the wrong computer? Would it even run? I don't know, but it's curious about the different ignition modules.

 

If you run across a Ford vehicle that has an IDM
(Ignition Diagnostic Monitor) fault code, this tip may be helpful.

The TFI module (Thick Film Integration, which refers to the type of internal circuitry used in this module) has been used on the
EEC-IV system since its inception.

There are two different module types, and, even though they may look alike, they are not inter-changeable.

One type is referred to as the "PushStart" type,
the other is called the"CCD" (Computer Controlled Dwell)type.

The "Push Start" module gets its name from the 4th pin on the module connector, which is a start signal from the starting system. When the module receives this 12 volt input, it increases or "Pushes" the ignition coil dwell for maximum coil output for easier starting.

The "CCD" module does not use a start signal input, but does rely upon the ECM Spout input to control ignition coil primary dwell.
By the way,ECM Spout controls ignition timing on both module systems.Under normal running conditions, the"Push Start" module starts the ignition coil primary dwell time about 3.5 milli seconds before the next anticipated coil firing.
At this point the module is waiting to see the Spout signal voltage change from low to high. When this happens, current flow to the coil is stopped, which will result in the coil firing. If the time is longer than 3.5 milli-seconds, the module will reduce the primary current to prevent the coil from over-heating, since it cannot anticipate the next coil firing.

The "CCD" module relies solely on the ECM Spout input to change ignition coil primary dwell time.

On this system, the trailing edge of the Spout wave will start the primary cycle,while the leading edge of the next wave will end it, resulting in the coil firing.
The time in between signals is the dwell.
Both modules are used in systemswhere they may be mounted on the distributor, or, they may be remotely mounted away from the distributor (commonly called "Closed Bowl"versions).

Usually, the "Push Start"modules are gray in color, while the"CCD" modules are black.
IDM is a feedback signal generated by the ignition system and is monitored at pin #4 of the ECM.
Its purpose is to diagnose missed ignition primary pulses at the time the ECM commands the Spout signal to fire the coil. Since it is used solely for diagnostic purposes, if this circuit is not operating properly, it will not affect vehicle driveability.

Both "Push Start" and "CCD" systems produce an "IDM" signal, however, they do it in different ways.
The "Push Start"system uses an external 22K ohm resistor (22,000 ohms) that is usually taped to the wiring harness that is connected to the negative terminal of the ignition coil. This resistor is used to lower the voltage of the Tach signal being supplied to pin #4 of the ECM.
This external resistor is not used on the CCD system since it is part of the internal circuitry of the module, which produces the IDM signal. So, the IDM signal travels from pin #4 of the module directly to pin #4 of the ECM.
Oddly enough, the "Start" pin on the"Push Start" module is the same pin as the IDM pin on the "CCD" module.
While the connectors are identical, inter-changing the modules may or may not create a driveability problem , while tripping a fault code of #18, or # 212 (IDM code).

These are problems consistent with inter-changing one type module in place of the other.
Identifying the correct module for your vehicle can be accomplished in a number of ways.

First, always refer to the correct application in the Engine Management catalog.

If that information is not available, check the wiring of the vehicle. If pin # 4 of the module gets a start signal (which should be battery voltage) from the starter circuit, it's a"Push Start" system.

On the other hand,if pin #4 of the module is wired directly to pin #4 of the ECM, then it's a CCDsystem.


Please excuse the length. I thought it was necessary to fully explain the differences between the black and gray modules.

 

Thank you thelonerangerxlt for the imput. I've heard that but
understand it better this time. If I determine that my vehicle does take the black module What do I ask for or what info do I give the parts man to be sure I get the right black module. They've
already told me the one I have is the one for my vechicle. They say it list the same one for several different years. Thanks again.
Come on back.
Just Jack

 

Do you get any other memory codes when you scan the system?
The pinpoint test in the Ford shop manual says that if you dont get a P0350, P0351, P0352, P0353 or P0354 then you have a "loss of IDM" and you need to replace the PCM. If you get any of the other codes in memory then you check the plugs, wires, cap, coil etc.

 

Thank you franklin2 for your input the other day. It doesn't seem they would put old stuff in a newer vehicle but, who knows?
Thank you racerguy. Like I said I have checked everything or it has been checked. It's got a new pcm that cost over three hundred bills from detroit. It was put in after the light wouldn"t
go out. It runs very smooth. The only code it has now is the
p1351. Same code it had before we put in the new pcm. When I figure out what spcs to give them at the parts store I am getting another ignition module. Although the one in
it also came from detroit for one hundred thirteen dollars. I'll get the next one at Auto Zone or Advance Auto Parts.
Come on back
Just Jack

 

Take a look at this thread too....it is for an older truck but it has a similar problem.... https://www.ford-trucks.com/forums/s...hreadid=109560

 

Racerguy,

I checked out that thread. I drew some hope from it. If it could be that easy. I'll check all those wires out. Could be something like that. I did install some new plug wires sometime before this problem came about. I may get to this tommorrow, Sat. for sure.
I'll not give up. Thanks. I'll let ya know what happens.

I'll be back
Just Jack

 

Crossfiring plug wires is a fairly common problem too after people replace the wires. They try to make them look all neat and tidy and then what can happen is 2 wires that fire next to each other in the firing order can set up an induction crossfire. The firing order on your truck should be 13726548. Plugs 6 and 5 fire next to each other. Make sure the 2 wires dont run parallel to each other or they can crossfire. Have them as far apart as you can and if they have to be together somewhere make sure they cross over each other and dont run beside each other. This can also cause a ping. I've seen it quite a few times after guys have replaced their wires.

 

Jack, don't buy a new ignition module just yet.

If your coil wiring harness is close to the sparkplug wires, Racerguy's suggestions certainly will apply.

If you have found the 22K ohm resistor (wiring harness on the firewall), then you have the "push-start" gray colored module.

For some reason, you're not getting a signal to the #4 pin on the ECM. This circuit comes from the negative coil terminal, through the 22K ohm resistor, to the #4 pin.

If you have a multimeter, check for continuity from the coil negative terminal, to the #4 pin on the ECM. You should read 22K ohms or thereabouts. If you read an open, then the problem is in this circuit; most likely a faulty resistor or open connection to the coil or ECM.

Let us know what you find.
Keep in touch.......

 

Hey, I know that you don't want to go through a lot of do this ,do that but I had a problem where my truck was killing on me and it was very hard to restart. Finally it would not start at all. I changed everything and nothing, so i called a friend of a friend who is a ford engineer. The first thing he told me was to run a seperate wire from the alternator to negative post on battery. The reason for this , he said was that the alternator was producing a field around it that interfered with the PIP signal in the distributor. It fixed my problem. I hope it helps you.

 

Thanks for the latest input from h8ford.
I don't think I have tried that but I have good news for everyone. I did check all those wires (plug wires and such) but there was no luck so I decided to take out the ignition module and just look at the pins.
They looked really good.
Then I said since I've got it out I'm gonna go hunt me a black one.
Of course we know that the Ford people said the gray one they gave me was the only one. I went to Advance Auto. The man went through his computer checking options and such. Found a part no. and retrieved it from his stock. It was a black ignition module made by Sorensen. I ask, does it say this one is for my vehicle?
He said "yes". I bought it, put it in (installed) and cranked it.
No light.
Cranked it several times, no light.
I've been driving it since Saturday and we drove it over a hundred miles today, "NO LIGHT". Thank the Lord.
Thanks to everyone.
Now I'm returning that $113 Motorcraft module.
YES I AM HAPPY.

Hittin The Sack
Just Jack

 

i have the same problem with my truck also.can you or still do you have the part number that you can give me on the mod.that you got from adv.auto.i have been trying to fix my 1351 code for 9 months.i call adv. and they said to ask you for this number that they havewhen you ot yours. thank you any help please.terry