Swap was running fine and now white vapor/smoke from one tailipe

[Jason Banks]

https://youtu.be/N1jBkT4DQAA

I have not had my swap running very long and it hasn't even been driven on the road. Started it up today and I have this happening.

Engine is a 6.0 with 862 heads that I bought remanufactured(heads only, I pulled engine from a running driving truck). Stock shortblock that I re-gasketed and installed the different heads and factory intake etc. Aftermarket wiring harness, using adapters to connect to the injectors, because the intake, fuelrail, throttle body and fuel injectors are from a 2003 suburban, that was running and driving.

My first thought at seeing this was, that's water, I have not run the engine very long and there had been a fair bit of condensation coming out everytime I start it. Last time before this was the longest I have run the engine.

I pulled the plugs on the passenger side and 3 of them looked blackish but dry. The 4th one had a dry tip, but I think the electrode had gas on it.

Stuck injector? Wiring problem? Still looks like water to anyone?

Before installing the injectors, I used a tool to pulse the injectors and run Berryman through all of them and they all seemed to work well. I also ran them through the ultrasonic cleaner. Maybe I messed one(some) up?