I re-read some of this post and the service manual today and getting more confused?
But I got some coffee in me now.
So I looked at diagrams. I think the lingo and locations got me crossed up. This EFI stuff is new to me too.
So the IAT (intake air temp) sensor is in the airbox. This is what you test at 68F and it was good. Yes the manual doesn't go less then 68F, I find that interesting but must be some logical explaination.
The MAP is on the throttle body and it tested with a voltmeter? Should be pretty easy. I would try this next. Sevice manual has wires and voltage info.
If that is good I would test the ignition coil when the machine is cold and see if your getting good consistent spark then.