I had the PCM update a few weeks ago for a different issue (battery management system problems). 4 days later I jumped on the throttle to pass someone one the highway and got the full limp mode with the wrench and check engine light displayed.
Was fairly humid, just under 0 degrees Celsius. Code p0306 was set. Brought it to the dealer, they said they had a fix for it. Turned out the fix was the same PCM update and removal of the air deflector plates. I said that I already had the PCM update, and they said that sine the deflector plates weren't removed, that's likely why it happened.
If I'm not mistaken, the purpose of the plates is to reduce the efficiency of the cac. So if this is the case, I shouldn't generate as much water. Couple this with the PCM update and the engine should be able to manage any water from the cac??
Long story short, I'm not convinced this is the fix we were looking for.