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Discussion Starter · #1 ·
1984 El Camino
350, 380hp. motor is pretty basic no emission or "junk" in there from the 80s, just basic setup.

Setting, This car was parked and gauge kept for 5 years, replaced battery no spark. I have around 10,000 miles on this motor and I put a brand new HEI GM distributor in, when we got the engine. Ran fine until I went to turn it over 10,000 miles and sitting inside for 5 years.


I’ve triple checked the power going to the Distributor while the key is both in “on” and “start” and have confirmed power is reaching the distributor cap. I even took it a step further and ran a wire straight for the battery as a test.

I have no tach, just a single wire to the "Bat" on the Distrubutor.

My first thought was the Coil, I took this with me to the store, could find none with a coil tester so I brought my meter with me and checked two coils and compared it to mine and readings were consistent. But I decided to buy the coil anyway since I figured under load perhaps it was a different story.

I’ve replaced the Cap, Rotor, Coil, and Ignition modal.

Tested jump plate with ohm meter on both wires. Both showed over 3Meg of resistance which is considered “Infinite?” so that checked out ok.

Confirmed the cap is turning with the engine.

Only thing left to check is the capacitor in there, which I could not find documentation for and it’s suggested since it wired in parallel it would not effect the operation.

After all the parts swap I still have no spark, even bought a spark tester today to confirm the results to be sure.

My father and I are stumped, something so simple but it just won’t give a spark. Any tests you could recommend?
 

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Have you replaced the rotor yet? They will burn a hole through, and send the spark straight to ground through the distributor shaft.

There is also a ground "strap"(solid metal) that goes from the center connection, in the 3 wire connector, pickup/module connector, and under the coil mounting. Without this, it will stall, and start back up after it cools back down.
 

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Discussion Starter · #3 ·
carsavvycook said:
Have you replaced the rotor yet? They will burn a hole through, and send the spark straight to ground through the distributor shaft.

There is also a ground "strap"(solid metal) that goes from the center connection, in the 3 wire connector, pickup/module connector, and under the coil connection. Without this, it will stall, and start back up after it cools back down.
Replaced rotor, The soild metal strap, if thats the little metal bar thats in the middle pin of the connector and goes down around the Coil (the coil sits on top of this metal bar) then yes it's in there, infact it has a new one of those as well that came with the new cap/rotor :)
 

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Discussion Starter · #5 ·
carsavvycook said:
The only other thing that would cause a 'NO' spark, would be the pickup coil in the distributor.

You should have spark, even if you were 180 degrees out.

AHHH! Where did you purchase the parts from?
Tested pickup coil with ohm meter on both wires. Both showed over 3Meg of resistance which is considered “Infinite?” so that checked out ok. We have a Mechanic friend coming over in the afternoon. I'll post the results.

The cap and rotor with 10,000 miles on it was GM new/old stock, have a GM parts manager friend that gives me any GM part at cost.

The new cap rotor is accel. Which by the way I was not impressed with, felt cheap, and the holes for the coil (where you push the pins down in to) weren't event machined all the way. I had to file it a bit to fit them in there. Cheap crap!
 

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What about the carbon conductor that transmits the coil power to the rotor?

There a rubber washer that goes on after the carbon button/spring assembly (which is removable) under the in-cap coil- this needs to be assembled correctly. Dielectric grease is used also.

The coil should have yellow (not white) and red wires.
 

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check the pickup coil wires for a break in them pretty common.Also you can test pickup coil function with a voltmeter set to a/c volts just hook a lead to each wire from the pickup and have ahelper crank it you should see an ac voltage.If this passes reconnect the pickup and hook a testlight from the tach terminal to ground have a helper crank the engine the light should flash if not suspect a bad module.If it flashes the problem is on the secondary side.
 

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ignition module, small flat "plate" (about 2" x 1") under the rotor. had mine go a couple of times. if this is the problem make sure when you replace it you put a fair amount of grease under it between the two metal surfaces.
 

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the pickup should continuity through the two wires with about 700ohms resistance. also make sure the magnet on the pickup is really magnetic as I have had two of the cheap HEIs not fire cause the magnet was too weak.
 

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Have you checked the distributor gear and pin as well as the distributor shaft to be assured nothings broken? When I was a kid a neighbor had his 78 Z28 brought down to be checked out by my brother. The engine turned over fine but sounded rather sick. After a while it was determined there was no spark, so he dove into why it wasn`t sparking, after replacing it with a distributor he knew was good he discovered the problem, the camshaft was broken. Not to say this is your issue, but am saying when you`ve replaced almost everything and it still won`t spark, make sure it`s turning.
 

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If it has a four wire connector on the distributor unplug it and splice the green and black wires on the distributor side. This will bypass the electronic spark controller. Also check the green and white wires on the pickup coil they get brittle with age and can break. Hope this helps.
 

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Discussion Starter · #12 ·
Things are looking up

Looks like the problem is solved, I receive the Distributor tomorrow, after I install and test I’ll follow up, thanks all for the useful suggestions.

The mechanic friend came over today and remove the distributor to take with him. He figured it out in 15mins, which put me to shame. He told my father he tested the “yellow wire” and it had no resistance on it. I assume that’s off the pickup coil.

Now as I stated before I tested resistance on the two pickup coil wires. Each read 3Megs of resistance and on-line it stated both wires should read infinite resistance. I forgot what “infinite” resistance was, I read some where anything over 1M (1000k) resistance is considered infinite. So it checked out for me.

So why did he receive different results then I did? Perhaps dirt or moisture or some form of junk was making a connection giving me a reading when in fact it was defective? I’m not sure, but I’m quite puzzled why he received no readings and I did.

For Future reference what would be a better and sure way of testing this, and is this something common after sitting inside for long period of time?

Anyone see dirt or junk make a connection and do something like this?
 

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The coil also has a yellow wire- are you sure he wasn't referring to it and not the pick up coil?

In any event, the reading below shows the ohms between the two P-U coil wires. There is infinity between either wire and the distributor body. This P-U coil is known to be good.

BTW, that old pos VOM has worked every time I've ever needed it. I have a nice Fluke, I- for the life of me- can't keep batteries in it. Even turned "off" immediately after each use, before long it'll be dead again. Prob. should look inside it but, well, you know... :smash:
 

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