So my swap is complete except the engine wont stay running. I've already had an initial flash on the ecm and had the vats removed. It is an LS1 block with an LS6 top end. The motor was rebuilt all forged a couple years ago for a procharger set up. I've got good oil pressure, fuel pressure, and spark. The motor wont fire up every time. When it does run it's only for a few seconds and then it dies. The ecm is holding a problem code for the map sensor circuit. "MAP sensor circuit low output." I've checked for vacuum leaks and havent found anything. The boost gauge shows 10in vacuum when the engine idles. I have 5 volts at he map sensor plug. I'm not sure what to check next. Any ideas?