Vacuum at idle....
 

What's normal? My gauge runs off the OBD port and reports at idle, warmed up, no a/c

-20 to -21

I swear it used to be -26 to -28ish, because -20 is perfect on the srt and I remember thinking it was strange the my vacuum was so high (or low if you account for the negative)

You're good.

I see -18 to -20 warmed up.