No spark Mopar dizzy and FBO box & coil

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I should have thought of this "if this happens again"

Assuming it quit, assuming you have checked, and with key in "run" the coil NEG is once again "high" near battery voltage

SIMPLY CHECK from the case of the ECU to battery NEG. Any sizeable voltage there at all means "it ain't grounded."

I mentioned this, but keep in mind the CONNECTORS including the main one for the ECU. you might pull it off, visually inspect it, and give it (and others) the 'wiggle' test while running.

I too, "hate" when things work mysteriously. "Will it quit" at a very bad time? Of COURSE it will LOL
 
I will do that if it happens again, I am going to check the - wire on the coil all the way back to make sure it is ok and check for continuity also, along with the plug in for the ecu.
 
We'll after driving it in a 50 mile drive last week I again parked it in the garage. No start again a week later. I check voltage at coil with key on and 12.48 on -&+ side. I checked the battery voltage and it was at 12.25, so I put the charger on the battery. Came back half hour later, turns over much better, still no start. So I pulled the 2 wire connector to the dizzy off, with key on, touched the male end of wire to ground of the harness and heard a spark, plugged it back in and turned the key, starts right up. Now I am leaning toward the battery draw. I do have a relay hooked up to the battery for an electric fan that I took off, replacement is on the way and run a mechanical fan for now, and the relay was warm, so I check the toggle switch for the fan and it was switched on. I did charge it the last time it wouldn't start but I thought it was low from turning it over so much. I think it was a drain on the battery so that is now unplugged. Will have to see if it starts later in the week.
 
Did you ever determine from FBO whether it's supposed to be drawing coil current?

If you can get it to 'eff up' again, that is coil NEG measures "high" immediately check for voltage on the CASE of the ECU to ground. If it's grounded, and the coil is high, you may have a bad ECU
 
Yes I talked to Don at FBO, this set up trouble shoots just like the factory set up. I will try that if it does again.
 
OK if he confirmed that, it's either a bad box or the box is not grounded., OR it's a bad wire from coil NEG to the ECU connector
 
Yep I believe that is what's up, I found another spare box I knew I had but couldn't find so I can throw that on if/when it happens again.
 
i think iwouldcheck the connectionon my ballast resistor to see if 1 was not making a solid connection and broke down any fire i am having a simular problem with my MSD, im loosing power when i was setting timming a month ago it jumped retard , then went to advance , its a mechanical dizzy i think my 6al box is shot and not reading correct . what is this change the wires around do? i have never had this problem , but the box is 15 years old . i was going to get a 3:91 rear endto change in and out when we go to the track 1 1/2 hours away but ,no need when it wont read right . i had it flashing at 3500 to 4500 the other day before i put it away to figgure this out before i hurt something . 67 dart 273 do youhave an old working mopar ecu chrome box and set up harness laying around you may be willing to sell or let me try ?? i do have an electric dizzy here , i dont believe they work with an MSD dizzy do they? thats this weeks challenge for me .then we get diff rear gear pig .what does changing the 2 wires do?? any old 6alboxes laying around ?? pm me thru fabo please Jon 1 608 837 4427
 
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