This is all great information. Did we ever check for any codes?
It seems like the ECM is just not firing the injectors. All else seems to be able to fire the injectors but the ECM just doesn't pulse them when cranking.
I found this stuff specific to your engine. Let's go through each test as it states. It will have you check basically the same things you have but in a different way. What I suspect is you are grounding the injector and assuming that everything is okay. However, this doesn't take into account inputs into the PCM so this test should take us to the culprit of preventing it from pulsing.
Just running through this, I assume you either have an issue on Step 4 or step 5. Because of that, I included the A-4 and A-6 tests so that you can test those systems if the result is "No."
Make sure you review each of these documents before starting so that you can follow the diag path. The third page of each set is a description of the test so it is good to read that so you understand what it is having you test and why.
Long story short, I suspect something is telling the ECM that it is not okay to fire the injectors. IF this is the case, I assume we would have a code so if we have not checked for codes then lets start with that.
Keep me updated on what you find. I know if it frustrating but I think you are close.
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Tuesday, June 11th, 2019 AT 11:22 AM