ISX15 CM2250 IMAP sensor erratic, intermittent or incorrect

[Waterloo]

This may sound silly, but have you pulled your fuses, thinking the inline to the ECM, and replace with a new one? And I would go as far to replace all of the mini fuses in your fuse block and see if that helps. If you have breakers, replace them with mini fuses in areas that you may think could cause intermittent issues. Another thing, these systems, I forget the term...

My jake and ABS idiot lights would light up going down the road, and it was driving me nuts. I took the truck to the dealer and the only thing that popped up on their computer was the compass module. I bought one for $20 on eBay and it solved my electrical issue. My Jake and ABS system was routed through this stupid compass module. Maybe you have something like this going on. Just a thought.