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help with '78 ignition problem

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Old 07-02-2009 | 11:13 PM
  #1  
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tlsmith1999
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From: Royse City, TX
Default help with '78 ignition problem

I have a 78 5 spd US that is having a problem in the ignition.
History: On the trip to SITM my starter went out. The car could be pushed started fine. When I got home, I replaced the starter, and now I have a new problem.

The starter kicks over strong, the car starts, but as soon as you let off the key, it dies. If you hold the key in the start position, the car will run. (Car has not ran since I replaced starter)

I have rechecked the wires on the starter, they are clean and tight and as far as I can tell are mounted correctly to the starter. Two larger wires to S1, black wire to S3, and brown wire to S4.

After attempting to start it a few times, there was smoke coming out of the 0.6 ohm ballast resistor. On the premise that once you let the magic smoke out of a resistor it will no longer work, I have replaced both of them. I replaced one wire at a time to insure I did not re-wire incorrectly. Not getting any smoke now, but original problem is still the same.

- I have 12.4v at jump port.
- With key in the on position I have same at the wire to .6 resistor and .66v at the .4 ohm resistor. both measured with wire disconnected from it's respective resistor.
- The coil primary and secondary resistances are correct.
- With the key on I have 1.05v at terminal 15 on coil.
I have replaced the ignition switch with a known good one to insure it was not the problem.

I believe the parts in red above are bad per SharkSkins 16v trouble shooting guide, but have no clue what is causing it.

Anyone have an idea what I may have screwed up while replacing the starter??
Or a good idea of what I should check next??

Thanks again,

Last edited by tlsmith1999; 07-02-2009 at 11:15 PM. Reason: typo (either good wine, or poor fingers)
Old 07-03-2009 | 12:34 AM
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michael j wright
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From: carthage,mo
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Tim, dbl check your wires going to solinoid. Solid yellow should go to term #50 and Bk/ye should be going to term #16 these are marked on the back of your solinoid, mine were atleast. Don't know if this is your problem or not, but a good place to start, as it was the last place you were, so to speak.
Old 07-03-2009 | 03:45 AM
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When you took the ignition switch I installed as a temp and reinstalled it on your switch, did the plug in come apart? Did any of the wires come off the cup connection?
Old 07-03-2009 | 05:45 AM
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tlsmith1999
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From: Royse City, TX
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sean,
I replaced the switch you put on the car with the original switch before we left NC. I put that switch back on the car just to prove that the ignition was not the problem.
Old 07-03-2009 | 10:17 AM
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is it possible that you crossed the 2 small wires on the starter.
Anything smoking tells me there is something wrong with your work
Old 07-03-2009 | 10:49 AM
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From: Owasso, OK
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With your ignition in the on position you should have a minimum of 3 volts. Since you have less than 3 but more than 0, it appears you have a bad connection at the ignition box or on one of the resistors. Try cleaning all the connections, especially at the resistors.

Dennis




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