What does "way off" mean when referencing the BBQ Pit reader? Being a little more specific may help folks understand where the problem is. (Was the unit synced properly? Was your Pit up to temp and running steady yet, were you using another therm and getting a different reading.... what were the temp differences, etc..)
(When I was fiddling with my 732, I wanted to use two food probes for a double pork butt cook and had a problem when trying to get a food probe to read correctly when placed in the BBQ/Pit temp port. That bummed me out. I feel so confident that I can maintain a steady pit temp that I'd rather monitor two food probes like my old maverick let me.)
Of course I never did read the directions ... so I am only guessing that the BBQ pit probe is only to be used with that probe port. Maybe some more details will help with your issue.