The cold start injector only gets a signal during starter operation with the ambient temp below 58F.
Don't know where you live, but most likely it just isn't cold enough for cold start injector operation.

The signal to the EHA does 90-95% of the enrichment for cold starting.

If you disconnect the red/green wire to the coolant temp sensor & then operate the starter you should have that signal to the cold start injector.

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