A few weeks ago I went to start my truck (1983 F-250 351w) and it wouldn't light off. I figured I was low on gas so I added 10 gallons and still nothing. Figured maybe it was the fuel pump or something, since it ran fine a few days prior. I let it sit while I was out of town and just now got back to tinkering with it earlier tonight.

I went through the usual checks, and found that it's not getting spark at the plugs, nor at the distributor. I get power at the "BAT" terminal on the coil. I swapped coils with one I had laying on the shelf, but no change. I thought maybe it was the external resistor mounted on the coil bracket, but I can't find anything from the parts stores online catalogs (RockAuto, O'Reilly, etc).

The coil is a Motorcraft #D5AE-12029-AB, and it says "FOR BREAKERLESS IGNITION WITH EXTERNAL RESISTOR". The external resistor is Motorcraft #E0TF-18801-AA with a "648" at the bottom. This is a small barrel-shaped resistor with 1 wire/connector that connects to the horseshoe connector on the "BAT" terminal of the coil.

I cleaned off all connections to everything related to the coil, battery, starter, solenoid, ignition system and still not getting spark.

How do I test the resistor? I can't find a replacement anywhere, can I bypass it or swap it with another part number? Is there something else I should check?

Thanks.

 

EDIT: The Haynes Manual doesn't even show the resistor in the diagram. It shows a wire going to a noise filter from the BAT terminal of the coil, so maybe I was wrong in thinking that little barrell was the resisitor? I'm guessing the resistor is somewhere else.

Could the issue be with the ignition module on the driver's side inner fender? Is there a way to test it?

Thanks.

 

The little one wire cylinder is a condensor.
It is there for radio suppression.

The external resistor is a wire built into the harness.
If you have 12V while cranking and 7V+/- with the key in the run position the harness is working correctly.

I would say that either the ignition control module mounted on the drivers side inner fender is bad, or the ignition pickup inside the distributor failed.

You can try grounding the green (tach) wire and charging the coil, then watching for spark when you break the ground.
This will indicate a functioning coil.
If you have an Ohmmeter you can test the coil and the distributor pickup.

 

Thanks.

I swapped the coil for another one I had with no difference. I then tested both coils and both proved to be good. I have 12v cranking and 6.8v in run position. I have cleaned every electrical connector & terminal under the hood. I have removed all of the harness wrap under the hood and looked over each wire for damage and found nothing. I'm pretty sure the module is the problem, but I need to know how to test it. I cannot find any information on testing the module. If it turns out to be the module, I'll go find a junkyard unit and swap it out, I just don't want to buy another module and that not be the problem.

 

Most auto parts stores will test the IGN module.

At the junk yard be sure an get one with a blue plastic grommet where the wires exit the box

 

Mine has a brown grommet. Why get a blue grommet?

I prefer to test the unit myself. I've had some situations in the past where the auto parts store tested a part for me and told me it was bad, when in fact it wasn't. They just didn't know what they were doing. I'll take it to them if I can't find the info I'm looking for though.

 

Hmmmm .. I thought it would be blue on your year truck.

I dont think you can test the module your self.
Jim

 

I don't think you can test the module yourself either.

My distributor pickup reads around 700 ohms.
(but note, I have the blue grommet DSII system, NOT the EEC controlled DuraSpark III California model)

Edit; The posts on this page by subford may help.
https://www.ford-trucks.com/forums/4...-module-2.html

 

I'll double check the color, but I'm pretty sure it was brown. I didn't give it a good look when I was cleaning up the connectors because I didn't know the color had anything to do with its function. The unit may not be a factory part. It doesn't say Motorcraft anywhere on it, atleast not visible from where it's mounted. I'll pull it out maybe later tonight or tomorrow.

Thanks for the link.

On another note, when I pulled the seat & carpet a few months ago I saw a computer mounted on the floor under the driver's side of the seat. I didn't even know this truck had a computer since it was carbed. This isn't a CA truck, and it was made at the Twin Cities Plant.

 

The manufacture location has nothing to do with the fact it may have been ordered from a district in California...


All the Dura Spark units are color coded. (Ford and aftermarket)
This is a simple, visual way to identify them instantly.

This thread may help you with your DSIII trouble shooting.
I don't know much about them.
https://www.ford-trucks.com/forums/7...eshooting.html

 

Thanks. I just want to get the truck running again for now. I plan to pull the engine soon and rebuild it with alot of hi-po stuff that I've had sitting on a shelf in my shop for the past 2 years but haven't found the time to do it. I'll be gutting all of the factory emissions/wiring junk and putting a very simple ignition system in it's place via a billet HEI Distributor. If I had the spare cash to get some headers and a few little odds & ends I would have already pulled the engine out and started removing factory electrical/emissions crap.

I'm going to a local junkyard on Friday to check out a few 80-96 Ford trucks for various parts I need, so hopefully I can find a ignition module to try out for the time being.

 

Have same problem. Did switch icm work for you?

 

EOTF-18801-AA Connecting to my Resistor was severed not sure how, but now my truck won't start and no parts stores around me carry this part nor do any junk yards. Where would I go to purchase this part?? I have a 1986 Ford f150 351 Windsor 5.8L 4v H.O.

 

Most would not know what that part number is and as posted at the top the only resister is a wire as part of the harness.
Is that the round thing with 1 wire out the end?
If so it is a condensor see post #3 it will also tell you how to test the system.
Also post a picture of said part so we know what it is.
Dave ----

 

That is a radio suppression capacitor. I googled the number and found it here. You do not need this for the truck to run, it's just to take noise out of the radio.

https://www.fordpartsgiant.com/parts...-18801-aa.html