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I know there are a ton of no spark/Pertronix threads on here but I have gone through them and am stumped. Need some help’
I have a 68 with a 289, ran fine then died while driving. Hasn’t started since.
Tried everything can’t get a spark.
So I have a Petronix Flamethower II coil and Petronix distributor with Ignitor.
Somebody able to walk me through a step by step diagnostics of ignition to determine which part has crapped out, or do I just replace the whole dame thing.
I know points vs electronic arguments, not what I am looking for, just want the car running without replacing everything if I can.
Thanks for your help.
Jason
 

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You need a voltmeter. Cheap ones are at Harbor Freight or any auto part store. Under $20 is ideal.


Put the + lead (red) on the + connection of the coil.


Put the - lead (black) on the - lead at the coil.


Turn the key on. You should have 10 - 12 volts at the coil. note - you may have to "bump" the starter until the Pertronics is at the point where it simulates the points are closed.


Turn the key to start - you should have maybe 10 - 11 volts at the coil while cranking. You should see it come and go every time the Pertronics simulates points opening and closing.


If not then you have found the problem. You just need to figure out why after that. The meter is your friend. It will tell you where there is power, and where it isn't.






I know there are a ton of no spark/Pertronix threads on here but I have gone through them and am stumped. Need some help’
I have a 68 with a 289, ran fine then died while driving. Hasn’t started since.
Tried everything can’t get a spark.
So I have a Petronix Flamethower II coil and Petronix distributor with Ignitor.
Somebody able to walk me through a step by step diagnostics of ignition to determine which part has crapped out, or do I just replace the whole dame thing.
I know points vs electronic arguments, not what I am looking for, just want the car running without replacing everything if I can.
Thanks for your help.
Jason
 
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Disconnect the coil from the distributor, pull the negative lead off the coil. Turn ignition on. Take a piece of wire and ground the coil momentarily. When you remove that wire, if the coil is good, you'll get a spark. My $.02 is the POS ignitor took a dump
 

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Perform this:
Function Test for Pertronix Positive Ground Module

Tip: Turn the magnetic sleeve upside down it will rotate easily and still "trigger" the Pertronix spark.

I just went through this a few weeks ago.

The rest of the story:
I have three Pertronix sparkies. All three tested positive and fired the engine. I found it was the coil, that bit the dust.
 

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Okay, how about this one.....

Take your ohmmeter and put the red lead on the coil+ and the black lead on the coil-. You should have approximately 0.6 ohms + or -.

Move the black lead to the coil high tension tower connection. You should probably have somewhere between 8k-15k ohms.

If so, the coil is okay.

Disconnect the battery and turn the key "ON". Move the black ohmmeter lead from the coil tower to the battery side of the starter solenoid. You should have around 0.2-0.5 ohm.

If so, this establishes the circuit between the battery, through the ignition switch, and to the coil has continuity.

Last test... disconnect the coil wire from the distributor and ground it. Connect an ANALOG VOLTmeter with the black lead to ground and the red lead to the coil- and crank the engine.
If you get a constant voltage between 1 and 3 volts, the ignitor is shorted. If you get constant battery voltage, check for a bad connection or broken wire between the distributor and the coil.
If the ignitor is functioning properly you should get a fluctuating reading between 1.5 and 12 volts.

I note an analog voltmeter as you may not be able to see the fluctuation with a DMM.
 
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