Aftermarket ignition problems? Help

[jspurl3]

I have been having trouble with my ignition, first it would crank and run as long as the starter was turning then when I let off the key to run it would die. My mechanic said my ignition was not stock it was an electronic ignition with this module on the driver fender (Maybe called a TFI Module??). He replaced a bad wire and put a new one of those modules on it. It ran fine for about 2 days until I gave it some gas merging on the interstate and it died completely everything (lights, ignition, etc) I brought it to him again he put a new "module" on and it ran for about 3 blocks and died... Now it turns over just wont crank! Should I just trash the whole ignition setup and get something better (if so suggestion) or is there a cheap fix??? Sorry for the excessive details, I just want to be descriptive as possible.

Thanks! I am clueless when it comes to electrical

 

[ransil]

What year Bronco?

Does the module say Dura Spark on it??

Got pics??

 

[VBH289]

What coil you running? Do you have a resistor on it???
I had a Dura Spark setup on my last 66. Ran it with a Blaster 2 coil from MSD and that thing would MURDER those boxes. put a resistor on it, and it worked great!

 

[SHX669]

If you lost all power ; even intermittently it's probably the main power fusible link.
It's fairly common on these EBs - yours is 38 years old .
They're cheap and easy to replace . It's a generic part that any parts store should have.
The link is located at the starter relay. Cut the old one out , splice in the new one { I used shrink tubing and solider on ours } and you're good to go .
SHX
the most common Duraspark II box is called the " blue box" . Because The electrical connector ends on the box are blue.
Unless your consistantly turning 5000 rpm it's a good system . I'd keep it.
Not sure about the resistor thing - I'm also electrically challenged . We've had the duraspark II and Blaster II coils on both Broncos for 4 -5 years without a resisitor and haven't had any problems --yet .
Where in the " line " would you put the resistor ? I had to take the one out of the '68 because the Blaster coil wouldn't work with the resistor hooked up

 

[jspurl3]

Its a 1970 bronco 302

It has a motorcraft coil.

The old module was a napa. Ill try and post a pic in my gallery. I don't see how to post it in here. The one the mechanic replaced it with doesnt have a name on it. Its grey... Sorry the pic is bad its all I have on my phone from when I was looking for the part. I think it had 6 wires coming out the back

I dont know about the resistor where would it be?

I don't loose all power anymore. It turns over, just doesnt crank.


Thanks for all the help!!

 

[SHX669]

If you've lost all power ; even only one time ; I'd replace the link .
Cause It'll do it again . Maybe on the freeway , or at night when it's 10 degrees or when you've got buddies waiting or a hot date waiting. --
They're under $10 and easy to replace .
With age the wires create more resistance . Then we add CB radios, cd players, fog lights , halogen head lights. Stuff it was never designed for even when new ; let alone after 32 -42 years
SHX

 

[VBH289]

If you lost all power ; even intermittently it's probably the main power fusible link.
It's fairly common on these EBs - yours is 38 years old .
They're cheap and easy to replace . It's a generic part that any parts store should have.
The link is located at the starter relay. Cut the old one out , splice in the new one { I used shrink tubing and solider on ours } and you're good to go .
SHX
the most common Duraspark II box is called the " blue box" . Because The electrical connector ends on the box are blue.
Unless your consistantly turning 5000 rpm it's a good system . I'd keep it.
Not sure about the resistor thing - I'm also electrically challenged . We've had the duraspark II and Blaster II coils on both Broncos for 4 -5 years without a resisitor and haven't had any problems --yet .
Where in the " line " would you put the resistor ? I had to take the one out of the '68 because the Blaster coil wouldn't work with the resistor hooked up

You put it in the power side to the coil- donno why, every time I haven't I have had catastrophic failures with it. I mean, fires, completely melted modules, fused internals, weird-

 

[jspurl3]

Ok so I will check for a resistor on the +wire from the coil and replace this main power fusible link that is by the soleniod... (there is a phillips relay on a wire off the soleniod is that it? If so what do I ask for to replace it? Thanks again guys

 

[VBH289]

You bet ya! Good luck!

 

[Viperwolf1]

Ok so I will check for a resistor on the +wire from the coil and replace this main power fusible link that is by the soleniod... (there is a phillips relay on a wire off the soleniod is that it? If so what do I ask for to replace it? Thanks again guys

This is not your problem but the factory resistor is actually part of the ignition wire under the dash. It's almost impossible to measure it by voltage drop with the breakerless system. You really need to measure the ohms from the coil + to the other end on the ignition switch. Stock resistor is only about 1-1.5 ohms.

If you lose lights with the ignition then you have a problem with the ammeter feed loop. Could be the fusible link or could be any other connection in the loop between the battery side of the solenoid and the alternator. Check the connector on the passenger corner of the firewall (engine side) with the 2 big black wires and the small green wire. Those black wires carry all the current from the alternator to inside and back out to the battery. That connector sometimes cracks or melts from the heat of the current.

 

[jspurl3]

You put it in the power side to the coil- donno why, every time I haven't I have had catastrophic failures with it. I mean, fires, completely melted modules, fused internals, weird-

Ok my coil doesnt say which side is positive and negative... but one side has two wires going to the post. Where do I put this resisitor? Thanks

 

[VBH289]

Ok my coil doesnt say which side is positive and negative... but one side has two wires going to the post. Where do I put this resisitor? Thanks

You stick it on the one that is IGN on on the two wire side. One side is ground to dizzy, the other is tach and the last is IGN

 

[needabronco]

Explorer Serpentine Swap Questions?

1. Is it normal to have to 'clearance' the bracket on the drivers side for the TFI module, and the passenger side for the frame rail?

2. Can anyone post a diagram of how they wired the 4G alternator to the bronco ignition/RJM harness?

Thanks.

 

[jspurl3]

ok HOPEFULLY my last question!?! just got the resisitor in and it didnt come with any directions or any markings on the piece... Is this thing directional? Or will it work either way. It has a ground wire on one side if that helps. Here's the link to it summitracing.com

thanks!

 

[VBH289]

Nope, it wants you to plug your power on the no wire side and run the wire side to the coil. They are not directional.

As for the Exploder swap, Ill see what I can find.

 

[ransil]

Maybe I got lost in this thread but here is what I would do.
I would not throw parts at it or add parts or change parts the I have no idea what they are for.

Disconnect the connector power connector from the module on the fender.
Disconnect the Starter wire.

Here is a drawing:
http://www.therangerstation.com/tech_library/DurasparkII.html

Get a volt meter.

turn the key to and hold in the start position.
the volt meter should read battery voltage or close to it.

turn the key to run position:
The red wire will now read battery voltage or close to it.

Find the Batt side of the coil.
Read the voltage again in the start & run position.

report you findings.

 

[jspurl3]

If you lose lights with the ignition then you have a problem with the ammeter feed loop. Could be the fusible link or could be any other connection in the loop between the battery side of the solenoid and the alternator. Check the connector on the passenger corner of the firewall (engine side) with the 2 big black wires and the small green wire. Those black wires carry all the current from the alternator to inside and back out to the battery. That connector sometimes cracks or melts from the heat of the current.

Ok... so I looked over the other issue I have. I'm pretty sure my bronco's previous owner replaced the fusible link on the ammeter feed loop with a phillips relay type link for whatever reason. I want to replace it back to how ya'll say it should be. What size fuse should I run on it?
THANKS!

 

[Viperwolf1]

Ok... so I looked over the other issue I have. I'm pretty sure my bronco's previous owner replaced the fusible link on the ammeter feed loop with a phillips relay type link for whatever reason. I want to replace it back to how ya'll say it should be. What size fuse should I run on it?
THANKS!

Go to Napa and get a 12-14 gauge fusible link if you are using a stock alternator. It goes between the battery side of the solenoid and the black-red wire going toward the firewall.

 

[Swaayze]

Search "ford ignition coil resistor" web wide. I've spent hours in the last 2 days learning about ignitions trying to diagnose mine.

Here's what I think I've learned so far, but search and read:

You should have a resistor wire between ignition switch and coil which drops the voltage to the coil (factory setup). During starting the resistor is bypassed and allows full voltage to the coil but in "run" the voltage is reduced to protect (supposedly per some) the trigger mechanism (points or whatever you have, in my case a Pertronix) not really the coil (though it sure seems that the coil needs protection as well to me). If you don't have proper voltage to the trigger/module you will have issues and destroy stuff. You need to check your voltages at battery, coil + in "run", coil + in "start". You also need to know what voltage you are looking for from the ignition specs (my Pertronix is 8-16v which is very nice, many are much tighter and you need to be within parameters). Troubleshoot and correct resistance as req'd to get your setup within parameters. Remember too that your voltages will increase with alternator output. Also you may have a bad coil too. Here's a good site describing a bench test of the coil:

How to test your coil

 

[Swaayze]

Another question though:

Isn't the resistor wire typically between the switch and connector in the engine compartment? I'm getting batt voltage in "run" at the engine connector but only 5ish at the coil. This seems to indicate the resistor wire is the red/green section from firewall to coil (which would screw up the full voltage starting provision, yes?....though I haven't had starting problems). I have a '73 pretty much all original, would this be a normal possibility? Also, the connector is toast...anyone know where to get a new factory type connector?