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> Coil Failing?, New plug wires and now it runs rough?
Neptune
post Jul 8 2021, 08:04 AM
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So I Have a 70 1.7L
It was stored for 4+ years
Fuel has been replaced with fresh
Had a miss so decided to replace the standard maintenance ignition components. Replaced the spark plugs and found hole 1 was "wet" and carbon-ed up. Ran much better with new plugs. Continued to replace cap and rotor, because I had the new parts and they were worn. Dizzy has the OG Pertronix Ignitor setup in it.

Got new plug wires yesterday, put them on and now it runs like complete crap! I checked all the connections and they are all seated as they should be and its just garbage. So from what I can tell the issue isn't just in one hole and that brings me to suspecting the coil. It is old, I've had the car since '93 and I've never replaced it.

Open to all thoughts and suggestions...
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Shivers
post Jul 8 2021, 08:25 AM
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"Got new plug wires yesterday, put them on and now it runs like complete crap!"

Make sure of the firing order, it is easy to have two wires flipped and not notice It will run but it will run like crap.
Check the easy and free stuff first before throwing money at it.
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Neptune
post Jul 8 2021, 08:30 AM
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QUOTE(Shivers @ Jul 8 2021, 08:25 AM) *

"Got new plug wires yesterday, put them on and now it runs like complete crap!"

Make sure of the firing order, it is easy to have two wires flipped and not notice It will run but it will run like crap.
Check the easy and free stuff first before throwing money at it.


Ya I learned a long time ago to change plug wires 1 by 1 following the wire, so I know that isn't it. The missing/rough firing isn't constant, it is intermittent and swapped wires would be a constant rough running motor. Good idea though! Thanx.
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Shivers
post Jul 8 2021, 08:36 AM
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You could narrow it down by putting the old wires back on. If it is back to normal you know the problem

@Neptune
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Shivers
post Jul 8 2021, 08:42 AM
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You know how it is, just because it is new does not mean it is good. I did a tune up, points plugs and condenser, the engine was running bad. Did the tune up and still ran bad. Chased that dragon for hours. Bad condenser made it run bad at first and I bought a brand new Bad condenser.
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Neptune
post Jul 8 2021, 08:52 AM
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QUOTE(Shivers @ Jul 8 2021, 08:42 AM) *

You know how it is, just because it is new does not mean it is good. I did a tune up, points plugs and condenser, the engine was running bad. Did the tune up and still ran bad. Chased that dragon for hours. Bad condenser made it run bad at first and I bought a brand new Bad condenser.

@Shivers

Ya I hear ya, I think there is a built in resistance to "doubting" the new parts, these plug wires are copper core and not the cheapest on the block, but you are right could very well be the culprit!

You wouldn't happen to know the symptoms of a dying coil would you?
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Shivers
post Jul 8 2021, 08:58 AM
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Usually when they are going bad, and not dead, they will start up cold ok. But not long at all the coil body will start to heat up and the engine will start to miss. Depending on how bad it is will depend on how long you will be able to touch the coil @Neptune
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rhodyguy
post Jul 8 2021, 09:06 AM
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Does the ignition require a specific type of plug wires? Incompatible wires for the Pertronix?
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Neptune
post Jul 8 2021, 12:39 PM
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QUOTE(Shivers @ Jul 8 2021, 08:58 AM) *

Usually when they are going bad, and not dead, they will start up cold ok. But not long at all the coil body will start to heat up and the engine will start to miss. Depending on how bad it is will depend on how long you will be able to touch the coil @Neptune

@Shivers

I did notice that the coil was really hot yesterday, I touched by accident and I pulled away from it for fear of leaving flesh!
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Neptune
post Jul 8 2021, 12:39 PM
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QUOTE(rhodyguy @ Jul 8 2021, 09:06 AM) *

Does the ignition require a specific type of plug wires? Incompatible wires for the Pertronix?

@Rhodyguy

Not that is specified in any of the documentation and I've used many different types over the years without issue.
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bbrock
post Jul 8 2021, 02:52 PM
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QUOTE(Neptune @ Jul 8 2021, 11:39 AM) *

QUOTE(rhodyguy @ Jul 8 2021, 09:06 AM) *

Does the ignition require a specific type of plug wires? Incompatible wires for the Pertronix?

@Rhodyguy

Not that is specified in any of the documentation and I've used many different types over the years without issue.


Pertronix recommends non-metalic wires although I've read people not having an issue with Pertronix I or II. Pertronix III which is particularly picky. I'm not saying that is your problem, just pointing out that there can be compatibility issues with Pertronix, Flamethrower coils, and wires.
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euro911
post Jul 8 2021, 04:07 PM
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When using a Pertronix module, the coil for a 4 cylinder motor should have a 3-ohms of resistance on the primary winding between the + & - terminals (with any other wires disconnected).

The video below shows how to test a coil, but it's primary is only 1.5-ohms, so don't wory about his readings. The secondary winding should read in the 10's of thousands of ohms ... +/- 20k ohms should be OK.

Here's a troubleshooting guide from the Pertronix site ... http://www.pertronix.com.au/troubleshooting.html



https://www.youtube.com/watch?v=/g2HT1oGl990
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Neptune
post Jul 9 2021, 10:12 AM
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@Euro911 My coil tests right at 3 Ohms.

Put the old wire set back on and still having the same issue! I must have hit something(loose wire or the like), checked for vacuum line that may have been off but found nothing now it just has a random miss... Gonna pull the plugs and see which hole(s) are fouled. When this sucker runs it runs great but when its having a temper tantrum, it can be a bit exhausting!

Thanks for all the suggestions guys, and if you have any others please send them!
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StarBear
post Jul 9 2021, 10:14 AM
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QUOTE(Neptune @ Jul 9 2021, 12:12 PM) *

@Euro911 My coil tests right at 3 Ohms.

Put the old wire set back on and still having the same issue! I must have hit something(loose wire or the like), checked for vacuum line that may have been off but found nothing now it just has a random miss... Gonna pull the plugs and see which hole(s) are fouled. When this sucker runs it runs great but when its having a temper tantrum, it can be a bit exhausting!

Thanks for all the suggestions guys, and if you have any others please send them!

"When this sucker runs it runs great but when its having a temper tantrum, it can be a bit exhausting!" Indeed; why some of us that give our cars names give them female names.. (IMG:style_emoticons/default/dry.gif)
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Neptune
post Jul 9 2021, 10:26 AM
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QUOTE(StarBear @ Jul 9 2021, 10:14 AM) *

QUOTE(Neptune @ Jul 9 2021, 12:12 PM) *

@Euro911 My coil tests right at 3 Ohms.

Put the old wire set back on and still having the same issue! I must have hit something(loose wire or the like), checked for vacuum line that may have been off but found nothing now it just has a random miss... Gonna pull the plugs and see which hole(s) are fouled. When this sucker runs it runs great but when its having a temper tantrum, it can be a bit exhausting!

Thanks for all the suggestions guys, and if you have any others please send them!

"When this sucker runs it runs great but when its having a temper tantrum, it can be a bit exhausting!" Indeed; why some of us that give our cars names give them female names.. (IMG:style_emoticons/default/dry.gif)



I hear you loud and clear brother! (IMG:style_emoticons/default/lol-2.gif)
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