I have a 1972 F100 4x4 with a 360 in it. It has the Duraspark 2 module with the blue tab. Earlier in the year it had a problem where it would randomly just cut out and die while driving. Sometimes I could pop the clutch and it would start again, but other times it wouldn't start for probably 15 to 20 minutes then it'd randomly fire up while I was cranking and once it ran, it ran fine.

Occasionally it has had some bad misfires under a load like when taking off as if it wanted to die but didn't and I even had a problem where I was driving once and it would try to die every time I took off, but once I let off the gas and was stationary, it idled just fine.

So just for S and Gs I stuck the old cap back on, which looked okay. And I also changed the plugs again. It ran fine for several months but now I started getting some misfiring. Then last night it died but I was able to pop the clutch and keep it going. The ignition module was tested earlier in the year and tested good but I went ahead and replaced it with an extra one I had that also tested good and this morning it died at a stop light and wouldn't start for about 10 to 15 min and ran completely fine on my way home.

I don't get what could be wrong. This has a new coil which I replaced around December, cap looks good, rotor was replaced when I got the truck and doesn't have many miles on it. Plugs were replaced a few months ago. Wires were done a few years ago. I've only been driving it for a year though. Vacuum is all capped where it should be. Any help is appreciated. Sorry it's so long winded. Just wanted to get all the info in.

 

Still sounds like the ignition module to me. Next time it dies pull over to the side of the road. Pop the hood and carefully feel the ignition module. If I am right the module will be real hot. Douse it with some water you should bring to cool it off. It should fire right back up then. This did happen to the Genuine Ford modules back in the day but was more prominent in the aftermarket ones. The aftermarket ones had about 1/2 the electronics in them than the Ford ones. I remember Ford had a poster showing the difference. The part number was D9VZ12A199A. This had been replaced by 1U2z12A199AA. But I'm not sure the replacement has all the same electronics. I would call the places below with the D9VZ12A199A original part number for price, shipping cost, and make sure it IS a NOS Genuine Ford module.


Nos Parts Source *Fo

913.220.5746

art Number:

D9VZ-12A199-A
Seller:Mustangs, Etc. - View ProfileDescription:

Phone818) 787-7634
Tell them you found it on RearCounter.comPrice:Request Pricing
Email:Send Seller Email InquiryQuantity:1
Location:Van Nuys, California Map & DirectionsPart Type:NOS



Part Number9VZ-12A199-A
Seller:Kama Obsolete Parts - View ProfileDescription:Modulator Assy-
Phone763) 434-0123
Tell them you found it on RearCounter.comPrice:Request Pricing
Email:Send Seller Email InquiryQuantity:1
Location:East Bethel, Minnesota

 

1U2Z-12A199-AA (replaced D6AZ-12A199-A & B; D9VZ-12A199-A) .. Ignition Module - Blue (Motorcraft DY-893) / Available from Ford.

El Jeffe: Mustang's Etc. is HIGH BUCK! almost as bad as Bob Allen Ford.

The 3 step scenario of a failing DuraSpark ignition module:

1) Module overheats, engine dies. Module cools down, engine restarts at once.

2) Module overheats, engine dies. Module cools down, engine restarts in an hour...or so.

3) Sooner or later, usually sooner, the module overheats, BURNS OUT. Now the engine will not restart.

Taking the module to an autoparts store to be tested: Will test OK unless the little charmer has burned out.

In the 1970's, the modules were so unreliable that Ford techs referred to DuraSpark as NeverSpark!

Inside the dizzy is a stator aka magnetic pickup coil, it could also be the culprit. Ford techs back then replaced both the stator and the module.

D4PZ-12A112-A .. Stator aka Magnetic Pickup Coil (Motorcraft DU-1A) / Available from Ford.

ALL 1974/79 FoMoCo V8 vehicles with DuraSpark except 1979 LTD/Grand Marquis 351W with EEC (Electronic Engine Control aka onboard computer).

 

You might try looking down the carburetor and working the throttle when it won't run. Is it squirting fuel? Maybe it's a fuel problem.

 

Thanks for all the feedback. I'm about to put a new engine in the truck so I might just warranty this Borg Warner module for a new one to see if it can hold me over.

And yeah I believe it is squirting fuel. I haven't looked recently but before when it died I did look and it was squirting fuel.

 

Ah. I'm glad you mentioned the stator Bill. I meant to on my post but got wrapped up trying to find out the 12a199 replacement number. Then forgot.
OP, as Bill mentioned the stator could be at fault also. The pic below is one I borrowed off the net of the Ford Stator. You see that blue magnetic area? If that is loose and giggling around on your rig that is Prolly the problem.

 

Does it not have spark when it won't start? If you have a spare module, why not just plug it in when it won't run and see if that's the culprit. Diagnosing is always better than just guessing and throw more new parts at it.

 

I changed the module to the spare one but that one's must also be bad because it died for 10 to 15 min right after I changed it. I have no idea how old it is or where it came from though because it was in the truck when I bought it.

 

Thanks! I'll check it out to see if it's giggling around.

 

Do you know what the odds are that 2 modules both fail with those exact same symptoms?
Here are some good basic diagnostic tips
How to Troubleshoot a 1977 Ford Duraspark ll Ignition System | eHow

 

I once had a Dodge PU and the ignition module went bad the same way: it would start & run fine until it got really warmed up (this was in the summer) and then after I turned the ignition off, and returned after a short time it would not start until it sat for a half hour. Also have a motorcycle with magnetic pick up coils and, when those went bad it would start up an run great for 10-15 minutes and then die, and then after 45 minutes, start up again. So, from my experience, it could be either.

 

With 2 used OR new aftermarket modules...the chances are GREAT. Trust me.
OP, after you find out the problem(s), please chime back in with the results.

 

Will do. I really appreciate all the feedback. It sucks that I'm just going to have to test it out and see if it dies but that's my only way right now!

 

Hmm... your experiences are a lot different than mine. I was in the garage business for many years when most Fords were running around with blue grommet and probably 95% of the failures of them I saw it died and never started again. Quite a different deal on the Dodges, half the time if one died in the summer it would restart after cooling off.
Odds are pretty safe if you changed a part and still have the same symptoms, it wasn't that part...Trust me

Just about any aftermarket module (or voltage regulator) is junk IMO. I'd rather take my chances with an oem Motorcraft from a junkyard.