Issues with IGF circuit, getting P035x codes for all cylinders

Hey folks, I've done a lot of reading on the IGF circuit, a fair amount of due diligence, and i'm still stumped, and bricked.

2008 tacoma with the 4.0.
I replaced the head gaskets about a week ago. That repair went fine, but the entire engine was apart, including all electronic components of the EFI and coils. In the process I took apart and reassembled maybe 4-5 times as I was troubleshooting various other things. I replaced all spark plugs and the truck ran perfectly after.

Engine ran well, consistently. I had to remove the intake and the fuel rail in order to address a coolant leak on the rear of the engine, after which i get a crank/no start, with P0351-P0356 codes for all cylinders. It seems likely i just jostled something, but i can't find it to save my life.

I completed DM93's diagnostic listed here:
https://www.tacomaworld.com/threads/2nd-gen-information-diagnostics.784008/#post-28042157

- I've tried disconnecting each coilpack individually in case one has failed.
- I have 6.5v at all cylinders on the IGF circuit, red and white wire, and continuity between them all. Does that voltage seem high?
- There's nothing resembling the J12 connector inside the firewall, just a big fatty square one for the entire harness, then it breaks out into separate connectors for the ECM. and since there's voltage in the circuit that means it's coming through wherever that connector would have been anyways.
I'm not seeing any abrasions or issues with the wiring, and I have voltage.


I don't have an oscilloscope but i can get one if need be. What are the other options, ECM failure?

- Any advice on how to test ECM? Seems like a random time for the ECM to shit the bed.
- Any advice on where the IGF wire enters the ECM?
- Other things i'm missing?

 

Does it start and stall or does it not even try to start?

 

Hot damn, it's the legend himself!

Not a single fire since it became an issue. Tried starting fluid just to see, nothing...

 

So we're probably not dealing with an issue on the IGF circuit but instead a Power, Ground, or Control issue to the coils.

Have you verified Power on Pin 1 (Black/Red) and Ground on Pin 4 (White/Black) at the coils with a test light?

The Ground for the coils is at Ground Point EE on the back of the passenger cylinder head.