Sniper EFI + Dual Sync - No Spark (was a driving truck)

[KyleSeal]

On Tuesday, I went out to start my '67 and it would not start at all. Cranks over, seemingly strong, but no spark - not even a slight kick off.

So I will lay out all the information I have:

ISSUE: no spark at all when cranking

Base info; 1967 C10, 350 V8 / 700R4. Sniper 1, Dual Sync distributor. Boyd Fuel Tank with in-tank fuel pump. New American Autowire full harness. Optima red top battery (dual post as Holley suggests).

Handheld data (when cranking):
-Fan 1 & 2 - OFF
-AC Shutdown - OFF
-CTS, *F - 98
-IAC POS% - 58
-AFR, A/F - ranging from ~15.2 - 14
-Battery Volts - ranges from 10 volts (millisecond at 9.8) but seems to show consistently 11.2 volts (when cranking) - WHEN THE KEY IS IN THE 'ON' POSITION, NOT CRANKING, BATTERY IS 12.3V
-RPM - 140-148
-CL Status - OpenLP
-Learn Status - NoLearn

Testing done:
-Inline tester on coil wire to cap - no spark when cranking.
-Pulled white wire as per diagnostic tree provided on the dual sync, grounded white wire, inline spark tester shows (seemingly strong) spark.
-Checked fuses - nothing blown.
-Checked connections, pins, crimps, no issues, burns, loose connections or melted connectors noted or seen at this time.
-Checked inside distributor - no burning or damage noted
-Replaced with good ignition coil - no change
-Tested for power at the positive wire to ignition coil on a test light - tests good

Background information:
-This was a running truck the day prior, ran good and quite solid I might add.
-I did have an issue on the way home the last time I drove it, the truck randomly died without event, and I coasted to the side of the road. Smelled fuel. Inspected under/around truck, no leak, truck restarted and ran fine. The key was left on during the coasting I did, and AFR went super lean (I suspect the Sniper thought it was still running so it was still recording). Never lost electronics (radio, headlights, dash)
- I was still in learning mode, as the truck just got to running in June, and this is a Sniper kit that had never been run, I bought it back in '21 with hopes the truck would be on the road earlier than now.
- I replaced the oxygen sensor the weekend prior due to AFR going rich when in overdrive and throttle applied.
-I had noticed for a few weeks, when the truck is at operating temperature, the IAC will sometimes surge up to 50-60% randomly and try to 'push me through a stop sign' when stopped. It would almost sound like a camshaft surge, to liken it to something.

Tasks I performed when installing the Sniper + Dual Sync combination:
-Sized alternator through American Autowire with my given accessories.
-OHM'd each plug wire after building
-Referenced all wiring diagrams
- NEVER guessed at wire placement, always consulted tech or a known good shop
-Power & ground directly to battery
-Kept all wiring from RFI potential areas
-12v crank wire to a 12v crank source (as confirmed by American Autowire tech)
-Shielded all wiring subject to head with either Earls heat shielding or other heat resistant sleeving
-Visually checked for fuel at throttle body
-Can hear fuel pump prime/run when key is actuated, sounds normal as it did

My suspicions I am trying to either disprove or confirm:
-Either a bad ECU and I am lucky I made it home with hot dinner, so far I do not see any at home tests for the ECU
-A battery with low cranking voltage.

At this time, this is all the information I have. Keep in mind, this truck cranked, ran and drove for multiple weeks before this issue occurred.

[Shifty One]

Being a low-tech guy, I'd make sure of the battery's voltage.

Is there a ballast resistor/resistor wire?

[KyleSeal]

Originally Posted by Shifty One

Being a low-tech guy, I'd make sure of the battery's voltage.

Is there a ballast resistor/resistor wire?

No ballast resistor here - to my knowledge the CD box delivers all spark commanded by the Sniper.

I have been charging the battery, so once I get home today I will see how it cranks with the battery 100% charged.