I had it running Good Idling and starting .Turned it off went out next morning and Just spins and NO START , 1986 Ford F-150 , 300 Inline 6 ...I hooked my test light up to #1 spark plug and see if it flashes, when I turned it over and NOTHING. Pulled the plug with Spark Plug installed and to see if there is an arc & No ARC...I unhooked the coil wire and leave it a little ways from where it plugs in and watch for arcing, Nothing ...Plenty of Gas I can smell it ...I have power going into the Distributor ,and Power going into the Coil pack...But No Spark to the plugs ...I don't want to throw parts at it ...I'm assuming its either the Ignition Module on distributor or coil ?...Thanks in advance !

 

Ok next test, pop the dist. cap and see if the rotor turns when you turn the motor over.
The dist. pickup turning should send a signal to the box. I know there is a way to test the pickup coil but I don't know it.
I would say the box is cheap enough and would not hurt to have one on hand. Buy 1 and use it as a test and if it does not spark hold on to it and look into testing the dist. pickup coil.
Dave ----


btw I would also pull apart all of the electrical plugs to the dist., coil & IGN box and check if in good shape.

 

Dave Thanks for chiming in -popped the distributor cap off Thurber the motor over and the Rotor and all components Turned ..

 

Check all the harness wires for loose connectors. Check coil wires and make sure they have a clean connection.

i thought usually when an ignition module failed, it dies when hot and will restart when cold, then slowly does it worse until it won't work when cold.

If you have a multimeter you can unplug the coil and check the resistance between all the connectors and see if its in spec, but I doubt the coil is the problem.

All the grounds between battery engine and body good?

If you have a duraspark 2 ignition, I have had one no start issue with the box where I took the small wire off the starter solenoid and connected it to the positive battery terminal. Then left the key in run, trans in neutral, and jumped the solenoid to start it and it worked fine. Ignition box was junk.

 

If still original, the 1986 will have a computer controlled distributor. The pick-up coil in the distributor may be defective. Since you had been "working" on the engine, to help it run well, and it failed to start the next morning, go back and check the last thing(s) you did and see if anything has come loose.

 

Your ignition module will be mounted on the distributor. It's the rectangle grey thing in the picture below.

 

Measure yellow wire going into ignition coil to ground/green wire while disconnected and cranking. Should see about 12 VDC. Make doubly sure wire between coil and dizzy cap is good (<5K ohm) and connections are gudentite.


I would also try to minimize pulling connectors apart because its cold and there's a good chance they'll break on ya

 

I don't know if they are the same, but I have a TFI module from a 1984 351W that I don't need. If yours is faulty and you can use it, I will send it to you. Just let me know.

 

After browsing and trying many things on this site. I figured I would throw this out there. I installed a new Distributor shaft in my distributor,and External Coil on my 1986 F150 , 300 INLINE 6 ..I have power going into the distributor....I have Power going into the External Coil .., I popped the cap and touched the Test light inside and it lit up ...I pulled a plug wire with the spark plug up against the block and No ARC ..Did the same thing with the coil wire with a test light attached turned the motor over an no light ...I have to be honest I'm lost when it comes to fords ...Any Help would be appreciated & Thanks in Advance

 

Fords and most other brands ignition systems work like this; Power is sent to the coil + any time the ignition switch is on, but it does not have a ground or negative to the other side of the coil. Power is also sent to the ignition module, whatever type you have. The ignition module is hooked up to the negative of the coil. It completes the ground circuit to the coil to fire the coil and create a spark.

The ignition module knows when to ground and fire the coil by the sensor inside the distributor. The spoked wheel, slotted disc, whatever it is, activates the sensor which sends a small signal to the ignition module. This small signal is used by the ignition module to know when to ground coil, or in your case and other Ford efi systems, the small signal is sent to a computer which modifies it for timing, and then sends it back to the ignition module who's job is always to do the hard work of firing the coil by grounding the negative of the coil.

 

Take the Module off and take it to an AutoZone and have it tested for free. Then check the coil.

 

The TFI module on my original '84 351W died all at once; no warning at all. I hear that they usually fail slowly when hot and work when cold, but that is not what mine did. It just died. Definitely have the module tested.

 

The TFI module on my original '84 351W died all at once. I have read where they usually die slowly, failing when hot and working again when cold, but mine died all at once. Definitely check the module.

 

I had this exact same issue when I first picked up my truck. My father-in-law said I could have it under one condition, it had to be driven off his property under its own power. I spent 2 weeks on and off in the afternoon working on the truck. The no spark condition it had wound up being a failing hall sensor in the distributor. Check out the site below for some diagnosis steps in your tfi module.

Part 1 -How to Test the Ford Ignition Control Module (Distributor Mounted)

If it is not the TFI module, its probably the distributor.