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Engine continues to run

Gas_Pumps

New Member
Car is a 66 and I have owned I since 68. It is a 289 automatic and has a Pertronics I solid state ignition system. Turned off and removed the key and it kept running. Disconnecting the battery stopped the engine. Could it need a new ignition switch or do I have a problem in the wiring? Could the Petronics be the problem?
 
Could be the starter solenoid. Next time it happens, pull the brown or green/red wire off the starter solenoid and see if the engine dies. If not, probably a bad ignition switch.
 
Could be the starter solenoid. Next time it happens, pull the brown or green/red wire off the starter solenoid and see if the engine dies. If not, probably a bad ignition switch.
With the Pertronics I it seems to start and run without the brown wire attached to the solenoid. Does that make sense? Also, an hour after it kept running everything appeared normal. It kept running in every position on the switch
 
You mentioned timing. Would it be too far advanced and how would that cause it to continue to run? Disconnecting the battery caused it to stop instantly.
 
With the Pertronics I it seems to start and run without the brown wire attached to the solenoid. Does that make sense? Also, an hour after it kept running everything appeared normal. It kept running in every position on the switch
That's most unusual and means something is mis-wired for sure or a bad ignition switch. Is this a Petronix I, II, or III?
 
Get a new ignition switch as it is almost assuredly the issue. The Petronix isn't going to keep it running like you are seeing. You might also consider upgrading to at least an Ignitor II to gain some benefit of the improved functions.
 
That's most unusual and means something is mis-wired for sure or a bad ignition switch. Is this a Petronix I, II, or III?
Pertronics One. This is the first time this has happened in 20 years. Doesn’t the pink wire get connected even in the start position?
 
Get a new ignition switch as it is almost assuredly the issue. The Petronix isn't going to keep it running like you are seeing. You might also consider upgrading to at least an Ignitor II to gain some benefit of the improved functions.
I will look into that. Thanks
 
Pertronics One. This is the first time this has happened in 20 years. Doesn’t the pink wire get connected even in the start position?
Doesn’t the brown wire only get full 12 volts when the starter solenoid is closed and the starter is running?
 
Doesn’t the brown wire only get full 12 volts when the starter solenoid is closed and the starter is running?
Yes, and it provides the 12V directly to the coil from the starter solenoid when the starter is running. When the starter is not running, the brown wire delivers the lowered voltage from the resistor wire to both the coil and the starter solenoid; the latter simply ignores the signal.
 
I've encountered this problem several times over the years. In every case, it has been the start solenoid.
Yep, Joe is correct, and it's easy to test for- if it won't turn off, take the wire off "I" on the solenoid- the small wire on the right side. If it stops then the contact to "I" is welded closed in the solenoid.
 
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