Is ballast resistor failure a myth?

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hotrod swinger

hotrod swinger

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All the chevy and ford guys are critical of the mopar ignition system, even mopar guys themselves, but I'm really starting to wonder about the suggestion that failing ballast resistors or ECU's or VR's are the problem. I can say from my experience that electrical problems are almost always bad connections, not components, especially not original factory components (I'm not including modern Chinese made relays, VR's etc. that often times do fail right out of the box).

Conventional wisdom says carry a ballast resistor and ECU around with you, but maybe it would be better to carry some extra wire and connectors and a wire cutter/crimper tool instead?

Personally, any time I have swapped in a part that "fixed" a problem, such as ECU, coil, etc., it didn't actually fix the problem, the problem eventually resurfaced. What happened is that the replacing of the component, tightening connections and moving wires around temporarily fixed a weak connection.

A ballast resistor is simply a resistor, no moving parts. How can it be considered an inherent weakness?

Carry an extra ballast resistor in the glove box? I say it's a myth, what say you?
 
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If It Starts then Dies when you let go of the Key, then it's bad. It's Rare. We know about it...
I've heard of guy's changing them because the Wipers stopped working and it Fixed it!
Myth
 
My grandfather had the factory one fail 30 miles from the nearest parts store, bypassed it with a gum wrapper (it was 1969). The car was two years old, I doubt it was a bad connection. Carry a spare, cheap insurance.


Alan
 
Had one die on my 71 Demon when it was only a few years old, 50 miles from home. We found a sweet spot for the key between start and run and taped it in that position to make it home.
 
55 years on the same ballast resister.

The support rod that the resistance coil sits on is even broken.

I think things like the amount of time the key is in the on position but the engne is off, the load of the ignition coil, the environment, (humid/dry) all play a part on component failure.


Side note...
If I was going on a long trip with my Dart I would bring another known good point distributer, a known good ballast resister, a known good alternator, VR. and fan belt.

And the needed tools to swap each.
 
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Not a myth- ANY part can and does fail. The frequency of failure has undoubtably been greatly exaggerated over the years, though. As said, many times it is the connection, ground or wiring that plays a role in any issue that surfaces.
I always have a toolbox in the trunk, and a spare ballast doesn't take up any appreciable room in it- if needed, it's there. Same goes for an ignition module and VR. Heck, it takes up less room than a spare tire, and when's the last time you actually used one of those?
 
I came across an original ECU, and ballast resistor when I was restoring my Dart. I have had spares in my trunk for 10 years. Originals are still going.
 
Wait until you have one go out.

You'll agree- not a myth.

At least it's somewhat easy to fix.
 
The ballast resistor is in line with the ignition. If it fails open (physical break) then it will cause the vehicle to stop running. No myth. It could be temporarily replaced in a pinch with a piece of wire, or anything that connects the two leads.

My convertible has a Pertronix unit in the distributor, that does not want a ballast resistor. So I replaced the resistor coil in the ballast resistor with a solid core copper wire to retain the factory appearance.
 
Mine failed once, replaced it with the spare I had in the glove box and drove off. I have since installed an MSD ignition with no problems so far.
 
Mine died last fall. Early rainy morning .Died at traffic light down the street from my house. Of course I just emptied my trunk 2 days before in preparation on installing a carpet so I had no spare. I jumped it out with a paperclip and made it back to get my spare. Wiring is good haven't had any issues.:BangHead: Just jinxed myself
 
You're brakes could fail too. Do you all carry a spare set of calipers and drum brakes in the trunk?

Or a transmission.

I bet a transmission fails as often as a ballast resistor.
 
I didn't read all the other post. My experience has been it's a myth. Of all the mopars through all the years, I cannot think of one instance where one failed. IF it happened, it was so little so long ago I cannot remember it happening. I do carry one because they are so small and cheap i think it's a reasonable thing to do. I've yet to call upon my spare ballast resistor. I've had more voltage regulators, alternators, fuel pumps, and water pumps fail and I cannot remember one ballast resistor failing.
 
Spare ballast resistor is 1.25" by 3", weighs about 2 oz and can be changed in about 5 min.

For that matter the ECM (and regulator) is only slightly larger, just as quick to change, and well worth carrying a spare of, too.

Slightly more involved with brakes.

...and with brakes you get a long warning period, unlike an instant electronics fail.
 
hotrod swinger said:
You're brakes could fail too. Do you all carry a spare set of calipers and drum brakes in the trunk?

Or a transmission.

I bet a transmission fails as often as a ballast resistor.
Click to expand...
But they're not something easily carried with you, or that you can change on the side of the road.
A ballast takes no more room or more difficult to change than spare fuses.
 
I had one fail back in the early 90's. The car would not stay running. I drove up to the Chrysler Plymouth dealership parts department in my little AMC Gremlin for a new one. I think it was around a buck, N.O.S. That means New Old Stock (not nitrous oxide) you dumbass laughing gas freaks. :poke:

The building is still there.

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doug 371 said:
not a myth
Click to expand...
In the mid 70's The dual ballasts failed quite often. As said above the cost was cheap and throwing one in the glove box was common. My 88 D 350 Ram still has all the original parts. I still carry one,along with a VR and Control box.
That way I will never need,the only parts that fail are the ones you don't have on hand.
 
I did have 1 fail on me in the 40 years of driving Mopars with the resister. Now this was with one of those accel super coils with the resister they supplied. So I don't know if that caused a bit more current draw or not. I put my original resister in its place and she held until I sold the car about 8 years later.
 
Had the run side fail on one back in the late 70's on my 73 Challenger. I wouldn't consider it a myth or a design flaw. It is just something that happens. A part failure. GM's HEI is a 12 volt system and doesn't use a ballast but they sure had their share of module and pole piece failures.
 
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