Ok, have a question for you all. Hooked up the PSB-1 boost/AFR gauge from Innovate today and I'm curious about something. I totally get how when the engine is running it's measuring the vacuum and it's negative -12 to -15 etc... Gas it and you can get it to zero. Assuming when I get this on the street and under load we'll see the boost being made. My question though is why would there be negative boost with the engine off? I even unhooked it from the boost line and just left to atmosphere and it's the same -6.2.
Is this normal? Why doesn't it read zero when the engine is off? I went through manual a few times and the only calibration I saw was for the o2 sensor. Just wondering if there is something I'm missing that maybe you guys are aware of before I reach out to innovate and ask. Thanks guys.