Help! no spark at coil

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myMoparHome

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I have a 68 dart with a 273, its been converted over to electronic ignition. been that way for over a year now it just wont start have no spark at the coil. its a new coil and i have power to the coil when the key is on tried swaping ballasts and ignition boxes with no change. I'm at a loss of why it wont fire?
 
It is possible that the coil is defective. What fires the coil is the grounding and opening of the negative terminal. You can manually do that with power to the positive side momentarily ground the negative post with a jumper and you should see a spark from the coil wire (if it is placed close to something on the car) when you open the circuit . If you have missing or bad grounds from various components and or the engine to chassis this will also cause above mentioned problem. It could be in the ignition switch circuit or the ballast resistor also. Another thing to try is with the key in run jump the starter relay terminals (making sure the car is not in gear!) and see if spark appears. If it does then something is amiss in the starting circuit (switch or ballast) area.
 
rlowande said:
could be pick up coil in distriutor
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^^^^ This too! Often the reluctor looses its oompf and or the gap is out of spec. A piece of heavy plastic like the clear hard to cut or tear packaging will make a decent feeler gauge. It needs to be about 0.006 thick and not ferrous hence the plastic.
 
This may sound funny but try to jump start the car and see if it will fire. Same exact thing happened to me a few weeks ago, left me stranded 130 miles from home. Checked ballast, checked and swapped coil, ignition box, reluctor had pulse. Nothing made sense why the car wouldn't fire. Decided to try and jump the car, fired right up. Weird as Hell. Drove it home, replaced battery. No problems since. Had the battery tested and it failed, yet the motor turned over fine just had no spark. Just a thought for you ....
 
Man, you poor non HEI guys pay for it over and over don't you? :D
 
"Work" all the connectors in/ out several times, pull them off and inspect with a flashlight for corrosion. "Feel" for how tight they fit.

Make ABSOLUTELY certain the ECU is grounded.

Turn the key to "run" measure coil PLUS and coil NEG to ground. The coil PLUS should be somwhere between 6--10 volts. If it's lower you have a problem, if it's "same as battery" you have a problem AND MOST LIKELY ECU is ungrounded

Coil NEG voltage should be fairly low, perhaps 1/2--2 volts. If it's zero, the coil is open or the ECU is bad. If it's way higher, near battery voltage, the ECU is not grounded or ECU is bad

If you have a tach remove that wire.

Remove the dist connector and take up the ECU end of the connector. With the key in "run" tap the exposed dist. terminal on the connector to ground. Each time you do that, you should get a spark.

DISTRIBUTOR

Especially "work" the dist connector in out. These are trouble. Check resistance of the pickup, should be 2-500 ohms. Set your meter to low AC volts---that is right AC volts and connect them into the dist. connector. Crank the engine. The dist pickup should "generate" about 1V AC

Inspect under the cap, inspect the rotor for "punch through." Inspect both for moisture, tracking, dirt, etc. Inspect the pickup and reluctor for "strike" damage, and rust and debri. Check side play of the shaft for wear.
 
67Dart273 said:
"Work" all the connectors in/ out several times, pull them off and inspect with a flashlight for corrosion. "Feel" for how tight they fit.

Make ABSOLUTELY certain the ECU is grounded.

Turn the key to "run" measure coil PLUS and coil NEG to ground. The coil PLUS should be somwhere between 6--10 volts. If it's lower you have a problem, if it's "same as battery" you have a problem AND MOST LIKELY ECU is ungrounded

Coil NEG voltage should be fairly low, perhaps 1/2--2 volts. If it's zero, the coil is open or the ECU is bad. If it's way higher, near battery voltage, the ECU is not grounded or ECU is bad

If you have a tach remove that wire.

Remove the dist connector and take up the ECU end of the connector. With the key in "run" tap the exposed dist. terminal on the connector to ground. Each time you do that, you should get a spark.

DISTRIBUTOR

Especially "work" the dist connector in out. These are trouble. Check resistance of the pickup, should be 2-500 ohms. Set your meter to low AC volts---that is right AC volts and connect them into the dist. connector. Crank the engine. The dist pickup should "generate" about 1V AC

Inspect under the cap, inspect the rotor for "punch through." Inspect both for moisture, tracking, dirt, etc. Inspect the pickup and reluctor for "strike" damage, and rust and debri. Check side play of the shaft for wear.
Click to expand...

Even squeeze that distributor connector on both female terminals a little to tighten them up.
The first time my connector gave me a no start I took it out and made a soldered direct connection there. (that obviously never happened again)
 
Check for power at coil while the engine is cranking and the key is in start position. We ran into this issue recently, had a issue with the connection at bottom of steering column. Hope this helps
 
update had some time today before it was dark! I have power at coil + with key in run will crank no spark, I can manully get a spark by grounding negative side of coil with the key in run but no spark when cranking engine.also dont know if this means anything tried several ignition boxes with no change inbspark when cranking but when boxes made contact with body groud would cause coil to spark ? God this is the most frustrated i have ever been with my mopars in 30 years. thanks for all the tips I will continue the fight again tomarrow!
Jeff
 
jcuda67 said:
i can manully get a spark by grounding negative side of coil with the key in run but no spark when cranking engine...................
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the ecu is not grounded!!!!!!!!!!!!!!!!! The ecu must be grounded!!!!!
 
jcuda67 said:
but when boxes made contact with body groud would cause coil to spark
Jeff
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Of course it did, LOL. The ECU MUST be grounded

OH!!!! didn't I say that already?

67Dart273 said:
..Make ABSOLUTELY certain the ECU is grounded.
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As someone above also mentioned MAKE CERTAIN you have battery voltage to coil DURING CRANK. "Crank" and "Run" are different circuits.

You can also run a jumper wire from a battery source to coil + DO NOT leave it hooked up longer than needed to test.
 
You could be loosing power to the coil in the start position or have an open circuit in that half of the ballast. If you have a test light hook it to the positive side of the coil and see if it goes out when you crank it.
 
Do you have to ground the ECU? Could that be my problem? LOL
 
It runs It runs swaped the distributor with another known working one and the engine now runs!!
 
I have news. That is not the problem. How I know? Your comment about touching the ECU box to ground and getting a spark. Either that or you had TWO problems.
 
67Dart273 said:
I have news. That is not the problem. How I know? Your comment about touching the ECU box to ground and getting a spark. Either that or you had TWO problems.
Click to expand...

Dangit Del, I was going to let that go since it runs now but NOOOO. :D
It could have been a bad reluctor, or out of adjustment and solved the problem with another distributor.
Or a bad connection at the pigtail I told him to verify that made connection when he swapped them.

Am I wrong?
 
TrailBeast said:
Dangit Del, I was going to let that go since it runs now but NOOOO. :D
It could have been a bad reluctor, or out of adjustment and solved the problem with another distributor.
Or a bad connection at the pigtail I told him to verify that made connection when he swapped them.

Am I wrong?
Click to expand...

He could easily have both problems, but the telling thing was talking about making a spark when grounding the coil NEG. With the key on and the box properly connected, the coils should already BE grounded, and then the comment about 'touching the box' to ground made a spark.

Thing is, guys, Model T's left the building some time ago. You have to pay attention to every detail about what you are doing. Have I ever made these mistakes? You bet your tail feathers.
 
It was probably grounding through something it shouldn't when it was running before and burned something up inside the distributor. duh.

Are yall turnin blue yet?
 
RustyRatRod said:
It was probably grounding through something it shouldn't when it was running before and burned something up inside the distributor. duh.

Are yall turnin blue yet?
Click to expand...

Go pick on the cat. Maybe he'll shiv ya
 
I get enough of that from around here.
 
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