No Spark or Fuel During Engine Crank

[Posi]

Disconnect the 4 wire plug at the ignition module and test the distributor side of the plug.

I've said from the beginning test from the distributor side.

Do the test again. D2 - D3

 

[Lumpy Grits]

I just checked mine and got 542 ohms, so yeah, that could be the problem. I am curious on just how it went bad. The could be an issue with the wiring or the plug so check that. The could also be a problem with the meter, since it is a sensitive circuit.

Seen this happen when folks don't disconnect the battery POS(+)when doing the install.
OLG

 

[thundley57]

I've said from the beginning test from the distributor side.

Do the test again. D2 - D3

My bad. Varying voltage on distributor side of connector while cranking.

 

[Posi]

The trigger wheel is working as it should.

Lets move on.
leave the 4 wire plug unplugged
Unplug the 2 wire plug
One probe to the red wire ( I believe with white tracer) other to ground (engine block).
"Not" the spades, ignition side.
turn key on

Post findings
also post battery voltage.

I may have to continue this tomorrow, still have a lot to do tonight and it's getting late on the east coast.

I recommend you purchase a new meter.

 

[thundley57]

No worries, wife insisted I take her to dinner so I'm done today as well.


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[Posi]

Here is the following test to do.

Plug both the 4 and 2 wire connector together
Unplug the distributor 3 wire connector.
Check ohms, probe the violet and orange wire on the distributor side.
If you “do not” find between 400-800 ohms replace the pickup coil
If you find 400-800 ohms you have a wiring issue between the 3 wire and 4 wire connector.

 

[Torxhead]

I would suggest checking the ohm gauge on your multimeter. Like purchasing a resistor in the range you are looking for and test it. The results will not be perfect but hopefully close enough.

 

[thundley57]

Seen this happen when folks don't disconnect the battery POS(+)when doing the install.
OLG

I disconnected the neg side of the battery during the Howell TBI install which was what was recommended.

I would suggest checking the ohm gauge on your multimeter. Like purchasing a resistor in the range you are looking for and test it. The results will not be perfect but hopefully close enough.

Yeah, had this thing forever, probably time for a new one. As mentioned earlier I tested the resistance on the resistor wire to the pos side of the coil and got 1.9 ohms. Tested the new wire I bought yesterday and it was also 1.9 ohms so subtracting the .6 ohms my meter reads when touching the probes together from 1.9 puts the resistor wire right about where it needs to be, 1.3 ohms.

The trigger wheel is working as it should.

Lets move on.
leave the 4 wire plug unplugged
Unplug the 2 wire plug
One probe to the red wire ( I believe with white tracer) other to ground (engine block).
"Not" the spades, ignition side.
turn key on

Post findings
also post battery voltage.

13.2 Volts, 2 and 4 wire unplugged, one probe to red w/white tracer the other probe to ground on female connector. 13.2 volts on battery.

Here is the following test to do.

Plug both the 4 and 2 wire connector together
Unplug the distributor 3 wire connector.
Check ohms, probe the violet and orange wire on the distributor side.
If you “do not” find between 400-800 ohms replace the pickup coil
If you find 400-800 ohms you have a wiring issue between the 3 wire and 4 wire connector.

Ok, couldn't help myself, after taking the wife to dinner went back over to the Mother-in-laws house (where the Jeep is imprisoned) to perform this test.

Tested resistance between the violet and orange terminals on the distributor connector (distributor side) and this time got 19.5 ohms with the icm connectors connected. I'm going to get a Echlin ignition coil pickup from Napa tomorrow and install it unless somebody suggests differently.

Really appreciating all of your guys help. I'm feeling confident that I'm getting it narrowed down thanks to you all!

 

[thundley57]

The trigger wheel is working as it should.

Lets move on.
leave the 4 wire plug unplugged
Unplug the 2 wire plug
One probe to the red wire ( I believe with white tracer) other to ground (engine block).
"Not" the spades, ignition side.
turn key on

Post findings
also post battery voltage.

Posi, were my results from this test posted above (13.2V) what you would have expected?

 

[Posi]

Posi, were my results from this test posted above (13.2V) what you would have expected?

Yes,
I had you test the red wire that runs from the ignition module plug to the ignition switch, you should have had battery voltage, in this case 13.2v.

 

[007]

 

[thundley57]

Thank you sir. I will replace my pickup coil in the distributor and post the results.


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[thundley57]

Just purchased a brand new distributor pick-up coil and while at NAPA tested the resistance between the orange and violet terminals. There was zero continuity, do these things need to be installed before registering continuity?

 

[Torxhead]

I think you have a bad coil. As I recall, you were not sure of your ohm meter either.

 

[Posi]

First, buy a new meter.
The pickup coil does not have to be installed to test.
You should have between 400-800 ohms.
What was the temperature when you ran your test?
The cold will effect your readings.
Make sure the pickup coil is warm around 70 degrees before testing.

 

[Lumpy Grits]

When was the last time you replaced the battery in your testing meter?
LG

 

[thundley57]

Ok sorry to continue the drama on this thread but here's where I'm at on this issue;

I purchased a brand new distributor pickup coil from Napa and un-believably it was bad and registered zero continuity between the violet and orange spades. Took it back and exchanged it for another one which read 580 ohms between the spades.

Installed the new pickup coil and now have spark and tach signal (electric fuel pump now comes on while cranking) and the engine now tries to start and has barely started a couple of times but still will not run.

The Howell TBI manual says that the above symptom may be caused by a voltage drop between battery voltage and the voltage to the ECM which should not be more than .5 volts while cranking. Mine has a 1 volt drop.

Question1: How much voltage drop (if any) should I expect on the heavy gauge red wire between the positive side of the starter solenoid and the ignition switch? I have a .6 voltage drop from the battery to the ignition switch (13.9 to 13.3).

Question2: How much voltage drop (if any) should I expect between the red power wire entering the ignition switch and the red w/wht tracer wire leaving the ignition switch? As mentioned above, I have 13.3 volts entering the ign switch but only 12.6 volts leaving the switch on the red w/wht tracer wire with the key on.

 

[Torxhead]

I did not have any operational issues, but I was getting about one volt less for everything in the inside of the CJ. I guess the problem was loosing a volt that came thru the CJ fuse box. This seem to be solved when I took the "sense" wire off the alternator that runs into the battery charge wire and connected it the hot line on the gas gauge and added a fusible link to be safe. I got this idea from a guy on another forum. I now get 14.8 volts throughout the Jeep.

 

[Lumpy Grits]

Was this PU coil from NAPA's 'Gold line'(top of the line)?
Did you ever get a better meter?
LG

 

[Posi]

Installed the new pickup coil and now have spark and tach signal (electric fuel pump now comes on while cranking) and the engine now tries to start and has barely started a couple of times but still will not run.

Good to hear the test I suggested found your spark problem. Don't get discouraged your other problems will be corrected.

It became convoluted trying to diagnose your spark problem the last go around with so many different opinions. I'll step back and keep an eye on this thread. Again, the problem will be corrected, it's not hard to figure out, and there are many knowledgeable folks on this forum.