I'm at a loss to understand what could be dumping that much fuel in for the 1/8th of a second I'm cranking before it starts with the CSI unplugged to make it run rich enough where a quick spray from the CSI floods the engine. There's just not enough time. If it were leaky main injectors, I would notice the smell and probably a really bad idle/performance during normal driving. It's sitting for 8 to 10 hours so I don't see how it could be related to off hours fuel pressure issues. AFM tested fine. I doubt there's enough time for the o2 sensor to make a contribution to fuel mixture, plus no o2 sensor code. IAC issue? Again, it tested fine too.

This is such an odd problem, it's the opposite of 99% of the cold start issues on the forums (i.e. csi not firing due to electrical or mechanical issues). So searching for "my truck starts better with the CSI unplugged" brings up zero results