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Discussion Starter · #1 ·
Hello,

My car didn't start this morning. I tested a couple of things but have reached the limit of my troubleshooting ability (which isn't much).

The car cranks but gives no indication of starting.

I'm not getting any voltage across the coil. I am getting voltage at the solenoid I pole when the ignition switch is in the on position. I didn't check but I assume I am getting voltage across the S pole or the starter wouldn't crank (is that assumption correct?).

I would guess I am having a problem with either the voltage regulator or maybe the solenoid. What else can I test to verify this?

I suspect the voltage regulator because it is the oldest ignition component. I also suspect the solenoid because I had a problem a few weeks ago where the car wouldn't stop when the key was turned off. This appeared to be a solenoid problem at the time but the problem didn't occur again so I didn't replace it.

The car has a new pertronix ignition and coil (2 months old), all new engine wiring and new solenoid (3 months old). I have had no problems until this morning except for the not stopping problem mentioned above.

Sorry for the long post, but I wanted to try to give all the important details.

Thanks much for any help.
Kevin
 

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More info needed..

do you have interior lights?

what other circuits work?

shouldn't be the solenoid
 

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Check for voltage at the coil+ with the switch in the RUN position...Then check the voltage in the START position. You should 8-11 volts in the RUN position and full battery voltage in the START position.

If this checks out OK, it's probably an issue with the Petronix.
 

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Discussion Starter · #4 ·
I did check that. I had a voltmeter on the coil positive and negative poles while my wife turned the key to the on position and then cranked it. I got no voltage readings at all.
 

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Discussion Starter · #5 ·
All the electrical is normal. Radio, lights, wipers, etc. all work as per normal. can't say on interior lights cause they didn't work anyway (g).

I am getting voltage on the S pole of the solenoid. I am definitely not getting spark. I hooked up my timing light and cranked it. No light.

From prior tests, no voltage at the coil. Assuming the solenoid is okay. My guess is the voltage regulator?
 

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It's probably not the voltage reg. that should only cause a dead battery. Remember, you need 3 things to make a car run, gas, spark and timing. Are you getting gas? take off the air cleaner and pull the trottle linkage and see if it's shooting into the carb, next try spark, I usally put a screw driver into spark plug boot (after taking it off a spark plug) and CAREFULLY hold it near a grounded part of the engine, make sure you hold it by the insulated part of the screwdriver. Have some one turn it over and see if you have a spark, I would suspect maybe a loose wire or maybe your new peronix(sp?) if you get no spark. Since your car was running I wouldn't think timing should be a problem. Start there.
 

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Discussion Starter · #7 ·
I know I'm not getting spark. I guess I could have multiple problems, but I want to concentrate on the no spark issue since I know that is a problem.

I'm not getting any voltage at the coil across the positive and negative poles when the ignition is in the on postiion or while cranking.
 

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Check the "bullet" connector that goes from the dirver side nfirewall to the Dist. I had this come loose once and had the same problem. I was lucky to spot it in about 5 min or it could have taken days to figgure it out, just a thought. this would prevent the coil from getting spark to the plugs.
 

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The small brown wire from the solenoid supplies battery voltage to the coil in the START position, it connects to the red coil+ wire at the firewall connection. You may have a broken wire or a bad connection.
 
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Check the positive lead on the coil to ground not to the neg of the coil with the key in the run mode.If no voltage the you have a wiring problem if voltage then it is ether your coil or pertronix
 

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I had the same problem with my car these past three days (I have the pertronix ignitor installed along with a flame thrower coil). The solution for me was to run a wire from the hot side of the coil to the hot side of the solenoid. Before I did this, I was able to start the car while in the starter position on the ignition switch, but the car would quit as soon as I let go of the key. If you run the wire and it solves your problem, disconnect it from the constant hot (12 volt) source and reconnect the other end so it is turned on by your ignition switch. If this works and you have any other questions, feel free to either email me or PM me.

Deathman68
 

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How did you wire in the pertronix? Which pertronix ignitor are you using (orig or 2)? And what coil are you running?

I just roasted my 2nd pertronix in 4 months. The first was my fault for running the original ignitor with a full 12V and high perf coil. The second one was an Ignitor 2, and I called pertronix, they said I was golden, but I killed it in about 2 months. So now, I have a Mopar ballast resistor sitting around, ready to be installed. Point being, don't rule out the pertronix being the culprit.

There is no reason for the voltage regulator to be the problem. The solenoid and ignition switch are also working properly. How do I know? The "I" terminial should still pick up the resistor voltage (8V or so) with the key in the "run" position. When turned to start, that "I" terminal should light up to 12V or whatever your cranking voltage is.

So, follow the "I" terminal wire, I think it Art said it was brown, to the main harness, and from there to the coil. I suspect you will find a broken or unpluged lead somewhere between. also, make sure your contacts are clean on the coil, and check the resistance of the coil to make sure it's not shorted out.
 

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the coil voltage comes from a" wired or" circuit created by tying 2 sources together: one source is 12 v from solenoid "I" terminal when ign key is in start position and goes away when key goes to run position; other source is fom 12 V bttery going thru wiring, ign key, neutral safety (auto trna), ballast resistor, and wiring back out to coil. lift coil + term wire and see if you get 12 v ( you do not get voltae drop of 4-5 volts with coil disconnected) with key in "run" position. if so your ok up to coil and look at coil/Pertronics, if not trace ckt. PM me if you need any more help.
 

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Discussion Starter · #15 ·
Thanks everyone for the help.

Since I wasn't getting voltage to the coil, I decided to see if I was getting voltage out from the ignition switch. I took the instrument cluster out and the ignition switch out. In testing, I found I was getting voltage. Then testing at the coil it was there too. I then tried to start the car and it started.

I assume I had a loose wire as some suggested or a flaky ignition switch. While I had it out, I replaced the ignition switch. It starts now but we'll see if it happens again.

Thanks again,
Kevin
 
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