# 69 GTO cranks but won't start



## Road Rat (Feb 2, 2016)

Just had a new MSB 'ready to run' billet distributer installed. Was out riding around and the car sputtered on any acceleration. At cruising speed it felt like there was a slight miss. Made one stop after 15 mins of driving. When I restarted it was a little stubborn, but did spark up and run. Made another stop 10 minutes later. It would not restart. Cranked fine, had a couple of brief sputters, but would not spark. Got it towed home. Charged the optimax AMG battery. Fired right up today. Battery reads 12.45V. Once running, reads 14.45V, which tells me the alternator is working( I think...). Voltage at the posts on the coil first read 1.68V. After the choke shut off and idled down to 850rpm, the voltage at the coils post dropped to 0.98V. Don't know if these volt readings at the coil post are ok. 
So, is the volt at the coil post Ok. Next, is it possible for the coil to work at startup and progressively get worse?
Any advice is appreciated.


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## Goat Roper (Oct 28, 2014)

I don't know if the '69 has the resistor wire in the loom but if it does you will need to add a relay to get a full 12V to the coil.
I took the Mallory out of my car that was in it when I bought it and converted it back to points and an original '67 distributor.
Lots of posts here about doing the conversion.


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## Road Rat (Feb 2, 2016)

Funny thing...I took the points distributor out for better reliability...huh.
So I should be reading 12V at the coil posts?


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## Lemans guy (Oct 14, 2014)

Road....test the coil with an ohmmeter...car off...or coil on bench....use ops to neg of tester on pos & neg of coil.....look for 1.6... Or 1.5 ohms...that is secondary winding...

Then use pos lead on pos side and Meg lead from tester inside top center spark plug wire hole.....11 and up is a good coil....13 real good....

7,8 or worse coil is bad.......if that is all good... Something in your power supply to the coil....does that new dizzy have Vacumn advance or is it a "Billlet" racing distributor?.....with no vac advance.....


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## Lemans guy (Oct 14, 2014)

Ps you need to use the 200 ohm stating on the first test....and the 20 ohm setting on the second test......it must pass this test to be good.....it is an easy step


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## Road Rat (Feb 2, 2016)

I'll do your suggested diagnosis this week. It does have vacuum advance


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## Lemans guy (Oct 14, 2014)

I do like the original dizzy...a module to replace points is ok....otherwise I don't know what those others really do...correct timed spark, at full power is what you need. 

One of the great nine guys,...maybe it was Lars..had a write up on the web about comparing a whiz bang dizzy against the standard ..on a Dyno....no difference


Performed the same".....


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## Road Rat (Feb 2, 2016)

To be honest, I waanted to go to electronic ignition and like the look of the MSD cap and wires. Prolly should have just stayed with the old set up. It ran fine before...


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## Goat Roper (Oct 28, 2014)

Road Rat said:


> To be honest, I waanted to go to electronic ignition and like the look of the MSD cap and wires. Prolly should have just stayed with the old set up. It ran fine before...


Funny, when I bought my car it was the first thing I wanted to get rid of because it was all original except for that dist.


I was able to find one and Ames had the period correct plug wires.
If you still have the original put it in and see if it fixes your problem.


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## Road Rat (Feb 2, 2016)

So I did the bench test and got 1.7 ohms at the 200 ohm setting. My multi meter does not have a 20 ohm setting, or is that just the first click on the dial, right before 200 ohm?

For the second test I should turn the ignition on and pull the coil wire correct?


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## Lemans guy (Oct 14, 2014)

RR...both tests are with no power, both on bench...or in car with everything off.....positive of meter to positive of coil, Negative to center connector on top...the spark plug like thing that goes to dizzy....you are testing resistance with the ohm meter..no power needed..

Look for 11 to 13... Good.....8, 9 bad.....1.7 is good.....on first test, not sure about your meter...20 and 200. Range...some meters may have auto ranging settings...


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## Road Rat (Feb 2, 2016)

So I'm looking for 11-13 ohms on the second test, not volts? Pardon me if I seem obtuse on this. I'm familiar with volts and amps, not ohms. I should prolly Google ohms so I understand the readings and what they mean. Thanks for the help diagnosing this.


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## Lemans guy (Oct 14, 2014)

No swear ohms just measure resistance in the wire.....if you touch your two meter probes together.....that shows no resistance....if you hold them in the air that shows absolute resistance.....a wire, or coil of wire, i.e. Your coil..has a specific resistance....

Also google how to diagnose and test an ignition coil..aa1 auto has a good diagram you can use and read more about it as well...

But if it is good you have to move on to other tests or the power supply to the coil,..make sure all of your ground, battery to engine to frame..etc all tight and no corrosion as well.


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## Road Rat (Feb 2, 2016)

Got both of my meters and neither has 20 ohm, but both have 20k. Tested the old coil pos. to coil element and read around 15.8 at first and dropped imediately down to about 8.0. Tested the new coil and it started at 18.8 and dropped right down to 9.6...both tests with meter set at 20k. Got no readings at any other settings. So it would seem that both the old coil and new one are bad. Having tested resistance, now have to figure out why such low voltage at the poles when running...and why the car runs fine at first, then starts to falter and eventually won' t start. I'll prolly turn it over to the mechanic next. Guy runs a speed shop and drag races a camaro...I would hope he knows what he's doing. 
I have enjoyed the lesson in multi meter use. Being a boater and rv'er, the only use I ever had before was testing voltage. I guess that's why they call it a multi meter, huh.


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