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Bronco randomly dying

Smedley

Sr. Member
Joined
Feb 28, 2004
Messages
928
Loc.
Snohomish
I am having issues with my Bronco just quitting on me. It has been running fine for a couple years now. It happens sometimes while driving, other times, just wouldn't start. I assumed it was my FITech and FCC2, so I pulled it and put on carb. Still having the same issue. Bronco will crank but not fire. I am getting fuel (also have used starting fluid). There seems to be no rhyme or reason to when or where it happens. I checked all grounds and connections. Replaced the coil. Battery is good, Centech wiring harness with a one wire alt. I do have a Crane ignition module (similar to a Petronix) that is probably 15+ years now. I've ordered a new Petronix and it is on the way. Any thoughts?

Thanks,
Will
 

DirtDonk

Contributor
Bronco Guru
Joined
Nov 3, 2003
Messages
48,105
I think you’re probably on the right track. Kind of all you can do at the moment anyway.
We know the specifications of a factory Dura spark for checking, but I don’t know how to check a crane module.
Coils are easy to test however, so don’t automatically change one for another because sometimes you add another layer of question marks.
However, here again, since a failing coil can go out intermittently, it’s not out of line to have just replaced it for testing.

Do you have a tachometer? You can also tell right away if it’s an ignition problem by the tach going instantly to zero when the engine dies even while you’re still rolling.

If you don’t have a tach, or even if you do, I would start by tracing all the ignition wires and looking for any splices or connectors that could be failing. I’ve seen corrosion buildup inside lots of crimp connectors even under shrink tubing and tape.

And if you do have a tach, disconnect it temporarily to make sure it’s not causing the problem. Because it’s connected to an ignition wire, a failing tachometer can kill a running engine.
 

gnpenning

Bronco Slave
Joined
Dec 26, 2011
Messages
2,269
Loc.
I have more questions than answers.
Have you done any voltage or ohms testing?

Disconnect the coil wire on the distributor side and put it close to a safe ground. Crank the motor over and check for spark. If no spark you will need to check power and continuity at the coil. If yes pull a plug wire from a spark plug and do the same test after putting the coil wire back on the distributor side. If no spark remove the distributor cap and check rotor and inside of distributor cap closely.

If you have spark to the spark plug check timing marks. Report back with your findings.

Do Paul's items as well.
 
OP
OP
Smedley

Smedley

Sr. Member
Joined
Feb 28, 2004
Messages
928
Loc.
Snohomish
Well. I swapped the coil. Attempted to replace the Crane module and realized that when I installed it I had to remove parts (long gone) that were now required for the Petronix. So I reinstalled the Crane. FiTech was still having issues, so I pulled it and threw on an carb and it has been running great. FITech is recommending I send the unit back for them to look at it and repair. It is well outside the warranty and am not sure I want to sink any money in it, if the carb is working well. I drive my Bronco daily but my commute is less than a mile.
 
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