Taken from ls1tech.com credit to joecar
Vacuum is related to MAP as follows: VAC = BARO - MAP
BARO is appox 29.9 inHg at sea level
Your MAP is 10.9 inHg
VAC = 29.9 - 10.9 = 19 inHg which matches your vacuum gauge reading.
So reading that I'd say my MAP is correct and I have no vac leak lol. Also i tested with starter fluid in the usual areas, no idle change. Also should mention I'm running 93 octane and have tried sunoco, shell, and citgo all with same results, still stumped. Luckily it is still under warranty so if I can't pinpoint it with your guys help they can figure it out haha
