I have an Innovate Motorsports digital boost gauge reading -75hg on a tvs2300 with just the key on and then -55hg vacuum with car idling...Im using the boost reference port as instructed (behind rear pulley on passenger side). Have stayed out of boost due to this issue as I dont want to break something lol. What could be wrong?

 

The sensor is bad or not set up correctly if you are getting that reading KOEO.

If it's PSIG it should read 0.

 

The damn gauge was not at factory defaults and had some odd settings that made it read wrong!! All good now