ok so my 79 f150 has had a large wiring issue that i have been dealing with section by section and first on the list was ignition and starter circuits...... so i laid out all new wiring, and followed the wiring diagram. right now ive got start circuit working perfect, but im not getting spark out of the coil. i ran 3 new wires from the distro magnetic pick up to the module, ran new power wires to the module and new wires from the module to the coil.... so far ive done testing and i have power to the module, in start and key on, so thats not an issue. and ive got 12v going into the batt terminal on the coil and in key on ive got power coming out of the coil on the neg side........ so the coil is good. i think that there is an issue with the magnetic pick up signal thats causing the coil to not get switched on and off. but im not sure....... anyone have any suggestions on how to figure out what my issue is. ive swapped out coils and ive swapped out modules and still no go..... any help is greatly appreciated....

If the orange and puple wires are reversed module will not work. So trace the wires one more time just to make sure everything is wired correctly.

ok big bronco, got that part straightened out now and thanks for that pointer, but now im losing power to the coil in key on, it will sputter and almost run in start, but then i lose spark @ key on...........

That is acting like a faulty ballast resistor going to your coil. During start the resistor is bypassed and coil gets full 12volts but in run position the power for coil is going through the resistor. Here is a wiring diagram that might explain it a little better.

the distro magnetic pick-up

What fixed mine. Mine would just about start, with key in start position, then
I'd loose spark in the run position. Sounds similar to your problem.

well why the hell do i need to use the ballast resistor???? i dont have one in my 77 and ive got no issues with it..... i mean its only a 1.0 ohm resistor, so i dont see how it would make a big difference in power to the coil. ill have to do a continuity check on the ballast resistor tonight.....

The reason it is in there is because the primary side of the coil is designed to give good spark while cranking. During cranking there is a voltage drop due to the starter. When engine is running and voltage comes back up to normal the resistor limits the coils current draw. I have seen people run with out them and have no problems, And some of fords ignition don’t use them. But basically it is there to keep the coil from getting to hot and burning up because of excessive current draw at normal voltages.

ok well i checked my ballast resistor, and it ohmed out fine.... and i even by passed it by just hooking the 2 leads to the ballast resistor together...... still only sparks in Key Start.... ive got power to the coil in both key on and key start, so the coil couldnt be the issue. my issue has to be in the key on circuit so i NEED some pointers here.....ive looked at diagram after diagram and im just not seeign where my issues could be......

hey mang, i still have all my stock stuff if your interested in it. it was all working when i took it off.


OR you could be cool :)

get a HEI dizzy conversion like mine. it cost me 65 bucks shipped off of ebay, and i couldnt be more happy about it. it dropped right in, and it works perfect :smokin:

one wire hook up, use the main power wire that was going to the electronic control module, and rip out the rest. make life easy on ya

im thinking ill pass for the moment on the stock wires, but i might take ya up on it later...... i would get the hei setup, but i have some different ideas for how i want to do the ignition setup....right now i just want to get the truck running so i can move it around the yard.........

no no not the stock wires. i have the stock dizzy and the control unit. cheap :D

distro is fine and if i end up needing a module ill just get one at autozone....though i dont see why i would need a module as it does spark in key start, which does mean that the module is switching to create spark at the coil......

Have you checked for spark while cranking? or are you checking for power to the coil? Does it not try and start then when you release the key fire once? If it does that replace the pickup in the dist.
Another possibility is bad ign switch.

ok im checking spark with an inbline spark checker and i LOSE spark in key on, but i have in in key start...... essentially the truck is running in key start mode, it just dies out when i go to key on........ i need to know if there is any way to test out the magnetic pick up????? crank motor and probe wires Z and Y ????? should get X voltage??? my dad (master electrician) and i (schooled mechanic) have looked over the circuit over and over again and dont see any reason as to why the truck wont stay running. i bought a new module at autozone tonight and that hasnt helped one bit. tomorrow its looking like my dad and i are going to lay a temp harness with 2 toggle switches and over lay all the needed wires, so that if the truck runs then we can start tracking down wires and looking for the shorted one(s). my dad has done it b4 with a similar vintage 351 on a bare chassis and got it to work no prob, which is why were are having such a tough time trying to figure out how/ why the truck wont maintain running. if anyone has any pointers PLEASE post them up, as im aty my last straw right now, bout to pull my hair out......

Here is something to try. Splice the black wire the one coming from your distributor and going to the module to a good ground. This is the only ground for your ignition module.

I got this off the net for testing magnetic pick up:

Connect the ohmmeter between the orange and purple wires. Resistance should be 400-800Ω. Next, connect the ohmmeter between the black wire and a good ground on the engine. Operate the vacuum advance either by hand or with an external vacuum source. Resistance should be 0Ω. Finally, connect the ohmmeter between the orange wire and ground, and then purple wire and ground. Resistance should be over 70,000Ω in both cases. If any of your ohmmeter readings differ from the above specifications, then the stator is defective and must be replaced as a unit.

Hope this info helps ya out.

ok my only question is how do i replace the stator thing if it is bad????? and where exactly is it located??? is it part of the magnetic pickup?????? im goinna go outside right now and see about doing those tests you posted and thanks alot, youve been a big help......

ok so i just got done doing some tests and ive verified that all of the items module coil magnetic pickup ect are all good....... took the main power wire to the starter off of the solenoid, and had my bro hold that to batt power to get the truck running and when i HELD the key in the START position the truck would run for as long as i was in KEY START...... so my issue has to be in the run circuit. something in the key start circuit is working properly, but the key run circuit is failing.......

The stator is the Mag pickup. Its the coil with the orange and purple wires on it.
Check with key on (in run position) and see if you have power on the red wire at ignition module. If not that is definetly the problem. I would find onother wire to splice into when the key is on to get the truck drivable.

to me it sounds like you have a bad ignition switch :confused:

to me it sounds like you have a bad ignition switch :confused:
no i have 2 known good ignition switches, and both of them are fine...... its an error in my wiring or the factory wiring is shorting out....... the magnetic pickup is working b/c i had the truck running by doing the hold key in start trick with the starter wire in hand and manually giving the starter power. by holding the solenoid contacts together the truck runs, as long as you hold the key in the start position..... big bronco i have power going into the module in both start and run.......

it is my understanding that the module advances timing a few degrees while power is being applied to the start lead of the module. Is it possible that you have the dizzy off a tooth, or just not timed right in the first place? You can wire the module to only have power to the white lead either in start or run and see if it will run like that. Just disconnect the red wire and tie the side that goes to the ignition switch back into the white wire somewhere. I have heard that it gets a bit of extra power due to the advance, but I have no clue if it is true. I have wired a few ford motors like this though, and had them run fine, although it tends to destroy modules after some time. Another thing I have stumbled upon is a tachometer causeing ignition problems, I had one ford that quit one day, and while trouble shooting I pulled the tach off the - coil terminal and it ran fine again, I never did figure out what caused it, but I assume the tach went bad. Good luck to you anyhow, I would defenitely try wiring the module for start only.

Later,
jason

i dont want to bypass this issue. i want to find my problem and FIX IT right..... the entire reason im doing all of this bullshit wiring tracking is b/c someone else hacked everything together and fucked it all up...... i just need some help figuring out what is happening thats causing me to lose spark in the key run mode........ the distro isnt off a tooth b/c the distro hasnt been fucked with and the truck was driven up to my house 2 weeks ago and all was fine...... my motor doesnt have a tach so that couldnt cause a no spark issue......

my point was to wire it like that temporarily and see if it runs, if it does, I doubt that your wiring is screwed up, but that the dizzy got turned. Also, you didn't wire the red run wire in after the ballast resistor, did you? The modules dont really like the 8 volts or so that you get after the resistor. Oh, and by the way, dont be an asshole. At the very least the info I gave you may help isolate your problem.

im not trying to be an asshole..... ive just been pretty damn testy after trying to to sort all of this out after a week and a half, and its taken up all of my free time.... gets harder and harder not to tweak as more and more peeps dont read what the hell is happening and just post something irrelevant (here and other forums) back on topic: the distro cant be off a tooth as the truck was running 2 weeks ago when i drove it up to my house. since then the distro hasnt been out. i took one step forwards by getting the truck up here to my house, then my bro swapped out the dead batt and fucked something up when he put in the new one and it wouldnt start. so ever since then im 8 steps behind where i started as now the truck doesnt run. the module is getting 12v power at both the white and red leads, just like its supposed to....... tomorrow im going ot run a momentary switch and a solid toggle switch in the circuit instead of the key switch to see if the key switch/ connector is whats fucking me up or not........

ok so i rewired things a lil bit to bypass the ignition switch and ran 2 switches instead and im still getting the same issue..... no spark in key run....... wtf is going on here????

:ghost:


HEI distributor will cure all your problems......
oooohohhhhohohooooooooo (spooky)

:ghost:

I still think your timing is off. I have talked to literaly dozens of guys trying to trouble shoot stuff like this and have heard it couldn't possibly be the problem, and in the end it was. if you really have no spark in run, then I am way off base, but my suspision is that you still do. IMO you are ignoring a big piece of this puzzle, and it is not that unlikely for a dizy to not be tight enough and to move or for something else to happen to put it a little out of time. Anyhow, that is the last I am going to say on it, have a blast trying to figure it out :D

well not to be an i told ya so, but i was correct in saying that i had no spark in run. we finally got the truck running tonight...... and it was the simplest most retarded thing in the world....... the Red lead and the white leads to the module are the power for key on and key start...... well we swapped it so that the white goes to the red lead and the red goes to the white and ta da the truck runs like a top.... eeeeerrrrrrrr kinda lol. the reason why this was so god damning hard to figure out is b/c if you look at the wiring diagrams it shouldnt be wired like this. so if we had kept looking at diagram after diagram we never would have figured it out, just had an outsider look at the situation and understand what was happening and (my uncle the outsider) said, well what would happen if you just swapped those 2 wires and sure enough......
yet again thanks for all those who had a valiant effort in trying to help me out on this one, as it was one hell of a toughie to sort out....

Good deal, I am glad you got it fixed! Now go wheel it, and break it again so we can do this all over again :D

Later,
Jason

Good deal, I am glad you got it fixed! Now go wheel it, and break it again so we can do this all over again :D

Later,
Jason


rotflmao..... this thing is miles away from being wheelable/ streetable......